Expert/Lay Opinion
Category > Expert/Lay Opinion
Updated 3/19/2024The trial court erred by allowing the lead detective to opine that defendant was the shooter.The trial court erred by failing to exclude the improper opinion testimony of the lead detective who was permitted to give an opinion on the most contested issue in the case – whether defendant was the shooter.id: 28218
Updated 2/7/2024The trial court abandoned its gatekeeper function by allowing the expert to testify to conclusions not supported by the material he relied on.The trial court erred by allowing a firearms expert to testify that bullet casings from two crime scenes were fired from the same gun. Abandoning its gatekeeping responsibility, the court allowed the expert to testify to conclusions not supported by the material on which he relied. The court further violated defendant’s confrontation clause rights by allowing the expert to testify that his findings were reviewed and approved by his supervisor.id: 27129
Updated 1/31/2024The trial court erred by prohibiting expert testimony on defendant’s susceptibility to give a false confession.The trial court allowed the defense to present a psychologist as an expert on false confessions and suggestibility generally. However, the court erred by not permitting the expert to testify about the results of an assessment designed to address defendant’s susceptibility to give a false confession or testify about the results of the psych test he administered to defendant.id: 28031
The prosecutor’s CSAAS expert erred by introducing statistical evidence of false allegations by children. Defendant was convicted of multiple lewd acts on a child. The prosecution’s expert, Dr. Urquiza introduced inadmissible statistical evidence regarding false allegations that went beyond the permissible scope of child sexual abuse accommodation syndrome (CSAAS). Defense counsel rendered ineffective assistance by not objecting to this evidence.id: 26164
Trial counsel erred by soliciting an opinion from the detective on the alleged child molest victim’s credibility. Trial counsel rendered ineffective assistance by asking the lead detective for an opinion regarding the accuser’s credibility. The detective testified that he believed the accuser was truthful, but police officers are not qualified to give opinions on the credibility of accusers.id: 26165
The trial court abused its discretion by admitting a prosecution child abuse expert to provide statistical evidence re false accusations.The trial court erred by admitting the testimony of a prosecution expert on child abuse, Dr. Anthony Urquiza, that studies show only four percent of child abuse allegations are false. The testimony had the effect of telling the jury there was at least a 96 percent chance that the child who claimed to have been abused was telling the truth. The testimony improperly invaded the province of the jury, but the error was harmless where the defense rebutted the statistical evidence through its own expert.id: 26121
The trial court did not err by excluding the non-testifying defendant’s self-serving statement made to the defense mental health expert.The trial court did not err at the penalty phase by restricting a defense psychologist from testifying as to certain details defendant provided to him. The details were significantly more exculpatory that the versions properly admitted into evidence, including those defendant provided in his police interview. Defense counsel made clear his intent to use the doctor to enhance defendant’s credibility, making it clear that defendant’s self-serving statements were being offered for their truth. Thus they were incompetent hearsay evidence. id: 25869
The trial court erred at defendant’s resisting arrest trial by denying his request to present an expert on excessive force.Defendant was convicted of resisting an officer under Penal Code section 69, claiming the officer’s use of excessive force negated an essential element of the offense. The trial court abused its discretion by denying defendant’s request to present the testimony of a use-of-force expert at trial. He has the right to present a defense, and this was not improper expert testimony on an ultimate issue. However, the error was harmless given the evidence of defendant’s actions before the claimed excessive force was applied.id: 25844
The prosecutor committed Sanchez error in proving that defendant was an MDO. People v. Sanchez (2016) 63 Cal.4th 665 holds that an expert’s hearsay statements to prove a defendant’s gang membership are inadmissible hearsay. Sanchez applies to cases involving mentally disordered offender commitments. The prosecution’s expert relied on multiple hearsay statements in concluding defendant met the MDO criteria. The order finding that he was an MDO was reversed.id: 25369
SVP finding was reversed where the evidence didn’t support the expert’s diagnosis of hebephilia.Defendant was found to be a sexually violent predator after one expert diagnosed him with hebephilia - a condition resulting in sexual attraction in pubescent age children, but not pre-pubescent or post-pubescent. The diagnosis was flawed due to the lack of information about the physical characteristics and/or sexual development of the victims. There was too great of an analytical gap between the data and the opinion offered.id: 24937
The trial court erred by excluding expert testimony on the heightened sensitivity to violence experienced by homeless people as the evidence was relevant to self-defense and imperfect self-defense.Defendant, a homeless man on trial for the murder of another homeless man sought to introduce expert testimony suggesting that homeless people are more sensitive to perceived threats of violence due to their higher rate of victimization. The trial court abused its discretion by excluding this testimony because it was relevant to defendant’s actual belief in the need to use deadly force to defend himself, and to the reasonableness of that belief. The evidence was also relevant to defendant’s credibility, and the opinion was a proper subject of expert testimony. The error required reversal of defendant’s conviction.id: 24939
Case-specific hearsay relied on by an expert was inadmissible after Sanchez. Defendant was convicted of multiple drug possession offenses. The prosecution’s expert witness, a criminalist, identified the drugs in pill form as controlled substances simply by comparing their appearance to pills pictured in the “Ident-a-Drug” web site. Following People v. Sanchez (2016) 63 Cal.4th 665, 679, expert testimony that is based on “case-specific hearsay” is inadmissible absent an applicable hearsay exception. Where general background (as opposed to case-specific) hearsay is involved, the expert may still testify about it as long as it’s reliable.id: 24920
The trial court violated defendant’s right to present a defense by prohibiting expert testimony regarding defendant’s PTSD at the time of the killing.Defendant was convicted of murder. However, the trial court prejudicially erred by prohibiting defense expert testimony regarding defendant’s psychiatric impairment (PTSD) at the time of the killing. Penal Code sections 28 and 29 do not preclude offering as a defense the absence of a mental state that is an element of a charged offense or presenting evidence in support of that defense. They preclude only expert opinion that the element was not present.id: 24701
Question of the expert witness improperly assumed an assault had taken place.The question to the expert about whether the assault was committed to benefit the gang was improper because it assumed that an assault had occurred. However, the error was not prejudicial as there was no suggestion that the expert knew what happened, and there was significant evidence showing that defendant committed an assault.id: 25497
Following Sanchez, the trial court prejudicially erred by allowing a gang expert to base his opinion on case-specific hearsay and FI cards produced during an investigation. The prosecution didn’t allege a gang enhancement (or charge the gang offense) but argued the killing was gang-related. The gang evidence produced here was comprised of a mixture of admissible background evidence, evidence that violated state hearsay rules, and evidence that violated the confrontation clause as described in People v. Sanchez (2016) 63 Cal.4th 665. Under Sanchez, the gang expert’s testimony that was based on his personal observations, knowledge and training was admissible as a basis for his opinion. However, hearsay statements that were case-specific such as other gang members admissions to other officers were inadmissible. Field identification (FI) cards referenced by the gang expert that were produced during an investigation were testimonial hearsay and inadmissible under Sanchez.id: 25347
Under Sanchez, which was decided just after the hearing, the experts were erroneously permitted to rely on hearsay as a basis for their opinions regarding a conditional release. Defendant, who had been confined in a state hospital for 20 years petitioned for a conditional release program. The prosecution presented experts disputing defendant’s readiness for such a release. The experts relied largely on hearsay to form the basis of their opinions. Soon after the hearing, the California Supreme Court decided People v. Sanchez (2016) 63 Cal.4th 665, where it found the basis evidence could not be based on such hearsay. Sanchez applied to his case that was pending on appeal, and no objection on these grounds was necessary because such an objection would have been futile under the law that existed at the time of the hearing.id: 25304
The trial court erred by allowing the prosecution’s expert to rely on massive amounts of inadmissible hearsay to support his conclusion that defendant remained an SVP. Generally, an expert may rely on inadmissible hearsay to support his or her opinion if reliance on such hearsay is reasonable for that purpose. However, the trial court prejudicially erred by allowing the prosecution’s expert to rely on massive amounts of inadmissible hearsay to support his conclusion that defendant remained a sexually violent predator, including evidence that defendant was “pushy” with a victim’s mother, testifying to the content of a study on testosterone’s impact on sex offender recidivism, testifying to the content of hospital records to support a conclusion that defendant was OCD, testifying to records showing defendant refused treatment, and to hospital notes suggesting defendant was nasty with staff.id: 24674
The trial court erred by allowing expert testimony in police use of force as the reasonableness of the officers’ actions was for the jury to decide and did not require specialized knowledge.Defendant was convicted of resisting an officer in violation of Penal Code section 69. The trial court erred by allowing expert testimony regarding police standards for the use of force as the issue of whether the officers overreacted during the incident didn’t require specialized knowledge and should have been determined by the jury. The mistake was aggravated by the fact that the expert gave an incomplete explanation of the law and emphasized the officers did what they were trained to do. The error required reversal of the conviction.id: 24569
The prosecutor erred by asking the gang expert whether defendant specifically committed the alleged crimes for the benefit of the gang.The gang expert impermissibly testified that the defendant specifically shot at the vehicle in order to promote or further the Norteno street gang. However, the error was harmless where the prosecutor also asked the expert a proper hypothetical that essentially elicited the same opinion.id: 24500
The trial court violated defendant’s confrontation clause rights under Crawford by admitting as “basis evidence” statements made by gang members during a police interview.The gang expert’s opinion was based in part on statements made by gang members during an in-custody interview. The testimonial statements were unreliable and presenting that “basis evidence” to the jury violated appellant’s confrontation clause rights under Crawford. However, the error was harmless where the jurors deadlocked on the gang allegations showing they did not rely on the expert’s inadmissible testimony.id: 24380
The trial court erred by excluding the testimony of the gang expert defendant presented to impeach the reliability of the state’s gang expert.The trial court erred by excluding a defense expert’s testimony proffered to impeach the reliability of the state’s gang expert. Contrary to the court’s ruling, the evidence would not have consumed an inordinate amount of time, and evidence questioning the reliability of the state’s expert was relevant. However, the error was harmless where the erroneously excluded evidence related mostly to the gang allegations that were subsequently dismissed.id: 24381
Any error in allowing the prosecutor to cross-examine the defense expert on the ultimate issue was harmless where the witness repeated that the issue was for the jury to decide.Defendant argued the trial court erred by allowing the prosecutor to ask the defense forensic psychiatrist whether he thought there was substantial evidence to support a psychiatric defense to the charges. Defendant claimed the doctor's negative response would be interpreted as a statement that he shot the victims with malice and after premeditation. Assuming that the question violated Penal Code section 29 which prohibits expert testimony on the issue of whether defendant had the required mental state, the error was harmless as the doctor had repeatedly emphasized the final decision on the point was for the jurors to decide.id: 19833
The psychiatrist’s opinion that defendant knew the difference between right and wrong was irrelevant at the guilt phase.The trial court erred by allowing the prosecution to ask its mental health expert whether defendant knew the difference between right and wrong because that evidence went to the sanity determination and was irrelevant at the guilt phase. The prosecution also argued the evidence was relevant to defendant’s mental state at the time of the killing, but the court did not address the issue finding any error in admitting the evidence would be harmless. id: 23242
The prosecutor’s radiologist was not qualified to give an expert opinion on whether brain abnormalities had an impact on defendant’s behavior. The prosecution’s radiologist was qualified to testify as an expert on medical imaging but the prosecution failed to establish that the doctor was qualified to testify regarding the effect of fossa abnormalities on human behavior. The trial court erred by admitting his testimony to the extent he opined defendant’s premature fossa did not affect his behavior. However, the error was harmless where the defense was lack of premeditation and the evidence that defendant acted with premeditation and deliberation was overwhelming. id: 23129
The trial court erred by permitting the prosecutor to question an expert physician about her opinion of the truth of the charges.The trial court erred when it allowed the prosecutor to ask an improper “hypothetical” question of the child abuse expert physician. The question was not hypothetical in nature and arguably asked the expert to testify directly about the defendant’s guilt as it mentioned him by name and asked about the expert’s views of the lab test results. However, the error was harmless in light of the other evidence of guilt, including defendant’s own statements.id: 23014
The trial court should not have permitted as lay opinion the witness’s specific testimony about what defendant would have told him.The trial court erred by allowing a witness to give the lay opinion that if defendant had been molested by the victim, he would have told the witness about it. It was the jury’s role to make that inference. However, the error was harmless in light of the overwhelming evidence of guilt. id: 22834
The trial court erred by precluding defendant’s psychiatric expert from testifying about defendant’s dissociation and the impact of that condition.Defendant was convicted of first degree murder. The trial court prejudicially erred by unduly restricting the testimony of his psychiatric expert. The court refused to permit the expert to testify about defendant’s diagnoses and mental condition at the time of the offense, and limited his testimony to diagnoses or mental conditions in the abstract and their effects on the general person in the population at large. He should have been permitted to testify that in his opinion defendant entered a dissociated state and the impact of dissociation. The testimony would have given the jury a basis to infer that defendant did not harbor malice, deliberate of premeditate.id: 22062
Hypothetical question to an expert incorrectly assumed that an event could have happened.The trial court erred by allowing a criminalist to testify that if a bloodstain found in the living room carpet was deposited by a person, the person must have been lying down rather than standing up. The question was improper as there was no evidence the stain was deposited by a person rather than an object that had been in contact with a person. The error was harmless in light of the evidence of numerous wounds and large quantity of blood in the room.id: 22053
The trial court erred by allowing an ICE agent to discuss the practices of drug trafficking organizations where there was no evidence that defendant was a member of such an organization.Defendant was charged with possession of marijuana for sale. An ICE agent provided lengthy testimony regarding the structures and practices of drug trafficking organizations, including a description of various roles that individuals perform within such organizations. However, because no evidence was presented linking defendant to such an organization, the trial court abused its discretion under Evidence Code section 352 by admitting the evidence. But the error was harmless given the strength of the remaining evidence.id: 22530
The trial court erred in allowing the experts at the MDO proceedings to consider an incident presented through unreliable hearsay in determining that defendant was a pedophile.The evidence was insufficient to show defendant suffered from the severe mental disorder of pedophilia to support the Penal Code section 2960 mentally disordered offender finding. In reaching their respective conclusions, the appointed experts each relied on a 1998 parole report which referred to a molestation incident in 1998 that was never charged as a crime or a parole violation. The report did not identify the source of the information regarding the incident. Evidence of the incident was unreliable hearsay and the court erred in ruling the experts could rely on the incident in forming their opinions. Without consideration of that incident there was insufficient evidence that defendant suffered from pedophilia.id: 18821
The court prejudicially erred in allowing an expert to present inadmissible profile evidence regarding the behavior of rapists.Defendant was convicted of several sex offenses against a single victim. The trial court allowed the prosecution to call a special agent with the California Department of Justice to testify as an expert on the issue of the behavior and conduct of rapists. In response to the prosecutor's hypothetical questions the witness stated defendant's conduct was the most prevalent type of conduct associated with rapists. However, the testimony constituted inadmissible profile evidence which overlooked the fact that certain behavior is consistent with both innocent and illegal behavior. The jury was invited to conclude that if defendant engaged in this behavior, he was a rapist. The error was prejudicial where the jury's verdict depended largely on whether it found the alleged victim or defendant more credible.id: 16515
The trial court erred by ordering defendant to submit to an evaluation with a prosecution psychiatrist after the defense experts testified.The trial court erred by ordering defendant to submit to a psychiatric examination by a prosecution expert after defense experts testified on his behalf. However, neither the discovery statutes nor the constitution authorize such discovery. However, defendant was not prejudiced by the examination or the prosecution expert’s testimony that defendant refused to participate in the evaluation, in light of the other evidence presented.id: 20501
A trial court may not order a criminal defendant to grant access for purposes of a mental examination, not to a court appointed mental health expert, but to an expert retained by the prosecution.The trial court’s order granting the prosecution access to defendant for purposes of having a prosecution expert conduct a mental examination is a form of discovery that is not authorized by the criminal discovery statutes or any other statute, nor is it mandated by the federal constitution.id: 20413
While a hypothetical question of an expert may not address the defendant’s intent, it may address motive.Defendant argued the trial court erred by preventing the defense psychologist from opining on a hypothetical question based on the facts of the case. To ask whether someone in defendant’s position would have had the specific intent required for robbery would have been improper because it would be the functional equivalent of asking whether defendant had the required intent. However, motive is different and a motive hypothetical would have been proper.id: 20331
The trial court erred by restricting the defense expert’s testimony as to earlier statements made to the parole psychologist because the expert was relying on defendant’s statements, not the psychologist’s opinion.The trial court erred in sustaining a hearsay objection precluding the defense psychologist from testifying as to statements defendant made to a parole office psychologist just prior to the present offense, that were relevant to the defense of institutionalization. The defense expert was not relying on the parole psychologist’s opinion, but rather on his notes of what defendant said during the interview.id: 20329
Officer without scientific expertise may not give an opinion concerning the results of a horizontal gaze nystagmus test.A police officer without scientific expertise is not qualified to give an opinion concerning the results of a horizontal gaze nystagmus (HGN) field sobriety test. Moreover, it is error to permit HGN evidence as the basis of an opinion concerning intoxication without a Kelly-Frye foundation, i.e., proof of general acceptance of HGN in the scientific community.id: 10605
The trial court erred by striking a question and answer regarding statements defendant made to a psychologist after the prosecutor's question opened the door. The trial court ruled the defense psychologist could not recount defendant's statements regarding the details of the crime. However, the prosecutor during cross-examination asked the expert to clarify how defendant could have lost focus on his original plan to steal and end up killing the victim. This question opened the door allowing the expect to discuss the defendant's statements. The trial court erred by striking the question and answer. The error was harmless where the jury
was otherwise fully informed of defendant's statements.id: 19461
Habeas relief was granted based on new statute regarding the admissibility of expert testimony on the effects of intimate partner battering.Defendant's 1991 second degree murder conviction was thereafter affirmed on appeal. In that case, the jury rejected defendant's claim of accident and the prosecutor's claim of premeditation. In 2001, the Legislature enacted Penal Code section 1473.5, which allows defendants convicted of killing abusive partners to present new evidence of partner battering. In the present case, the defendant was granted relief because a reasonable probability existed that if presented with expert testimony on intimate partner battering and its effects, the jury would have found defendant guilty of the lesser offense of voluntary manslaughter.id: 19432
Counsel was deficient in failing to challenge the officer's testimony expressing an opinion as to the definition of the crimes, the fact that the crimes were committed, and defendant's guilt.The opinions of the testifying officer as to the definitions of robbery and extortion, the fact that the crimes were actually committed, and defendant's guilt were improper. Defense counsel was deficient in allowing the officer's testimony to go unchallenged. However, counsel's failure to challenge the improper opinion testimony did not require reversal where the properly admitted evidence supported every element of the charged crimes and the improper testimony did not affect the outcome of the trial.id: 12286
Opinion testimony based upon an interview and standardized written personality tests is admissible.A criminal defendant charged with committing lewd and lascivious acts upon a child may introduce a psychologist's opinion testimony based upon an interview and professional interpretation of standardized written personality tests, that defendant displays no signs of deviance or abnormality. Such testimony is competent but disputable expert opinion rather than new scientific evidence that must be proven reliable before it is admitted.id: 13034
The court erred in admitting the police officer's testimony regarding the veracity of the victim's dying declaration.The trial court erred in admitting a police officer's opinion as to the veracity of a dying declaration. Although the officer's opinion as to the veracity of the declaration may have been rationally based on his perceptions of the victim's physical and mental state, it was not necessary to elucidate his testimony. The error was harmless as the testimony added little to the evidence the jury was entitled to hear and defendant presented little evidence to undermine the credibility of the dying declaration.id: 13036
Trial court erred in refusing to permit the defense expert witness to testify that defendant did not share characteristics commonly shared by pedophiles.The defense sought to introduce evidence that defendant did not share characteristics commonly associated with people suffering from pedophilia. The defense made an offer of proof that the expert witness, a psychologist, had examined the defendant and had administered several standard psychological tests. In the present situation, the defendant was entitled to have the doctor state his opinion that defendant was not a sexual deviant, or was not a pedophile, or was not likely to have committed the charged acts.id: 13040
The rule that lay opinion testimony must be based on the witness' personal observation does not apply to reputation testimony.At defendant's child molestation trial, defendant sought to introduce the testimony of two women character witnesses to the effect that he had a reputation in the community for normalcy in his sexual tastes, and in their opinion he was a person of high moral character. The rule that lay opinion testimony must be based on the witness' personal observation does not apply to reputation testimony and the evidence should have been admitted. Moreover, evidence of moral character as it relates to sexual morality is relevant to child molesting and should have been admitted. However, these errors did not require reversal where the evidence was not evenly balanced and there was little chance of a more favorable verdict absent the error.id: 13037
Court erred in suppressing a witness's statement that he had trouble remembering "because of his brain cells."A coperpetrator testified for the prosecution. The court erred in suppressing his statement that he had trouble remembering "because of his brain cells." Assuming the proffered testimony related to the witness's present cognitive difficulties, it was admissible opinion evidence under Evidence Code section 800, for there is no logical reason why qualified lay witnesses cannot give an opinion as to mental condition "less than sanity" or to similar cognitive difficulties. The error was harmless where defendant sought to introduce the statement to show the witness recognized his memory was impaired and the record showed the jury was made aware of the shortcomings in the witness's memory in other ways.id: 13014
An indigent defendant cannot be denied an expert she needs where no one with the appropriate expertise is on the approved panel of experts.An indigent defendant admittedly entitled to and in need of an appointed expert (in this case a battered woman syndrome specialist) cannot be denied her choice of experts solely because the one with the expertise she needs is not on the trial court's approved panel of expert psychiatrists and psychologists - notwithstanding that none of the approved panel members have experience in the specialty needed for the defendant's case.id: 12783
Expert testimony regarding battered women's syndrome is not relevant unless there is sufficient factual evidence that the victim is a battered woman.The trial court erred when it allowed the prosecutor to present expert testimony regarding battered women's syndrome. Other than the evidence of the present incident there was no other evidence indicating defendant abused or behaved violently toward the victim. There was no evidence that defendant fit the profile of a batterer, or that the victim and defendant were engaged in a battering relationship. Admission of the expert witness testimony was prejudicial where both the trial court and the prosecutor emphasized the expert's inflammatory testimony.id: 16036
Trial court erred in allowing a gang expert to testify as to defendant's subjective knowledge and intent to possess a handgun.Defendant was convicted of conspiring to possess a handgun. A police officer testified as a gang expert establishing defendant's membership in the gang, as well as his subjective knowledge and intent to possess a handgun. However, the testimony about defendant's subjective knowledge and intent was improper expert opinion on the ultimate issue, and the evidence was otherwise insufficient to establish that defendant was involved in a conspiracy to possess a handgun.id: 17057
Whether the seized vest constituted body armor was a subject for expert testimony beyond the knowledge of the experienced officer who testified.Defendant was charged with being an ex-felon in possession of body armor under Penal Code section 12370(a). The body armor was a bullet proof vest. At the preliminary hearing, the prosecutor argued that bullet proof vests, like firearms, are sufficiently within common experience to be identified at trial by lay witnesses such as the officer who testified, and was ruled unqualified as an expert. However, whether the vest qualified as body armor was beyond common experience and was a proper subject for expert testimony, even though the lay witness was highly experienced. The information was properly set aside. id: 19002
The trial court erred in allowing the battered woman syndrome expert to testify that she believed the co-defendant was truthful in allegations against defendant.A psychologist, who testified that co-defendant was a battered woman, further testified that she believed the co-defendant was credible in her accusations against defendant. The testimony was improper since expert testimony is inadmissible to establish credibility. However, any error in allowing it was harmless since defendant was not charged with any offense against the co-defendant, and the expert's testimony was not offered to vouch for the credibility of the co-defendant's testimony about defendant's role in the charged case.id: 18059
The court erred by excluding expert testimony that defendant was passive after the witness refused to say he was 100 percent certain defendant would not commit a violent act. The trial court erred by excluding the testimony of an expert who would have described defendant's passive personality. The court applied an incorrect standard by requiring the witness be 100 percent certain that defendant would not commit a violent act before the proffered testimony could be admitted.
id: 18958
The court erred during the sanity phase by failing to give a limiting instruction after the prosecution's expert testified that defendant said he could tell right from wrong. During the sanity phase trial, the prosecution's mental health expert testified defendant told him that he knew the difference between right and wrong. The trial court erred by failing to instruct the jurors it could consider the statements only to show the basis of the expert's opinion, and not for their truth. However, the error was harmless where the evidence of insanity was weak, and the possibility the jurors considered the statements for their truth was remote.id: 18977
The trial court erred in allowing a prosecution expert to express opinions on legal issues. The trial court at defendant's SVP trial abused its discretion in allowing the state's expert witnesses to opine on certain legal issues including whether defendant had two "qualifying
prior convictions" for "sexually violent offenses" involving "substantial sexual conduct," and whether he was likely to commit future "predatory" "sexually violent offenses." In testifying on these issues, the psychologist effectively instructed the jury on the law and how it should be
applied. This invaded the province of the jury and the trial court, and lacked foundation in his experience and expertise as a forensic psychologist. However, the error was harmless in light of the independent evidence which established the points.id: 19046
The dog scent evidence was improperly admitted because it lacked foundation and scientific proof of reliability.The trial court erred in admitting dog scent evidence because it lacked foundation and scientific proof of reliability. The dog handler was not a scientist and not qualified to testify about the characteristics of the "scent transfer unit" device he used, or its acceptance in the scientific community. While testimony of a dog's pursuit of a fleeing suspect may be admissible, dog scent recognition is a different issue requiring foundational support. However, any error in admitting the evidence was harmless in light of the compelling evidence of guilt.id: 17729
Court erred in failing to permit expert testimony on the effects of stress and expectancy on perception.Defense sought to introduce testimony of a psychologist to show that defendant's actual perception of events may have differed from reality due to stress and preconceived expectations about what might happen. The court erred in finding the studies in that area are not sufficiently reliable to permit such expert testimony. The court further erred in questioning the witness' credentials where she was basing her testimony on her reading of the work of others rather than her own independent research. However, the error was not prejudicial where the jury found defendant guilty of attempted voluntary manslaughter, rejecting a charge of attempted murder. Relying on a theory of imperfect self-defense, they necessarily accepted defendant's testimony that he believed himself threatened, but concluded such belief was not objectively reasonable.id: 11426
Updated 3/6/2024Prosecution expert’s penalty phase testimony on sexual sadism was not necessarily inconsistent with SVP Act and the trial court did not err in denying cross-examination of the expert with SVP law.Prosecution expert, Dr. Dietz, testified at the penalty phase of defendant’s capital case that sexual sadism does not impair an individual’s ability to control his or her behavior. Defendant argued this was inconsistent with the prosecution’s theory in SVP cases, but he failed to argue that point in the trial court. The claim that such testimony was misleading was also forfeited for lack of such an objection at trial, but was rejected anyway since experts often disagree, and Dr. Dietz offered a limited opinion. Next, the trial court did not err by excluding testimony concerning the SVP Act while cross-examining Dietz because it would not have affected the jury’s impression of his testimony.id: 26525
Updated 3/6/2024The trial court did not improperly limit the scope of defense counsel’s cross-examination of the prosecution’s expert on the issue of another witness’s demands where there was no admissible evidence regarding that fact.The trial court did not violate defendant’s confrontation clause rights by prohibiting the defense from cross-examining the prosecution’s sex trafficking expert about a witness’s demand for $15,000 and immunity for her testimony. There was no admissible evidence regarding this fact at the time of the court’s ruling. While a defense witness later testified to the other witness’s demands, the defense never sought to recall the expert to address the issue.id: 26567
Updated 3/5/2024Gang expert’s opinion was proper even though he had never heard of someone being killed for refusing to join a gang.Defendant challenged the gang expert’s testimony after he admitted that he had never before heard of someone being killed for failing to join a gang. However, an expert need not have personal experience with the precise fact pattern to offer a proper opinion. The expert’s opinion drew on his expertise about the significance of gang recruitment, jumping in ceremonies and disrespect.id: 26838
Updated 3/4/2024Prosecution investigators review of defendant’s jail visitation logs to learn of potential experts was not prejudicial.Before trial, the prosecution’s investigator reviewed defendant’s jail visitation logs and contacted persons listed. Through these efforts, the prosecution learned about two defense experts who were consulted but did not testify. Even if that was an improper invasion of a defendant’s statutory right to confidentiality in consulting experts, there was no prejudice where the prosecution did not learn of any conversations between defendant or defense counsel and the experts.id: 26969
Updated 2/26/2024The officer who had never seen methamphetamine infused paper in the prison was properly allowed to testify that the paper contained a usable amount of the drug.Defendant was convicted of possession of methamphetamine in prison. He argued the trial court erred by allowing the officer to testify that the amount of methamphetamine infused onto the papers found was a usable amount because the officer had never before seen methamphetamine infused paper or observed anyone ingest the paper. However, the officer could properly rely on his training regarding prison contraband to conclude that when an inmate placed a paper in his mouth to dissolve, there was a usable amount.id: 26237
Updated 2/26/2024Intimate partner battering instruction did not suggest that if jurors believed the expert they should believe the complaining witness.Defendant was convicted of several crimes involving domestic violence against his ex-wife. The prosecution presented an expert on intimate partner battering who described how victims often cycle back and forth between periods of seeking help from police and of supporting their battering partners, including by making false statements to the police. The instruction given on the subject (CALCRIM No. 850) did not suggest that if the jurors believed the expert they should also believe the complaining witness.id: 26278
Updated 2/23/2024CSAAS evidence remains valid and is a necessary component in the prosecution of child molest cases. In People v. McAlpin (1991) 53 Cal.3d 1289, the court found that expert testimony on the “common reactions of child molestation victims,” know as Child Sexual Abuse Accommodation Syndrome is admissible to rehabilitate such witness’s credibility when the defendant suggests that the child’s conduct after the incident- e.g., a delay in reporting - is inconsistent with his or her testimony claiming molestation. Defendant argued that McAlpin is out of date and changes in public perception of child abuse and decisions in other jurisdictions require a reevaluation of the admissibility of CSAAS evidence. However, CSAAS evidence is still valid and it is a necessary component in the prosecution of child molest cases.id: 26933
Updated 2/22/2024Failure to type blood at each location did not make crime scene expert’s conclusion as to the sequence of the killings speculative.The trial court did not err by admitting testimony of the prosecution’s crime scene reconstruction expert. Although the expert’s initial overview of the sequence of the victims’ deaths was not supported by specific evidence, the remainder of his testimony supported his conclusions. Contrary to the defendant’s argument, the blood at each location need not have been typed for the expert to draw his conclusion as to its source.id: 26958
Updated 2/22/2024The trial court did not err by permitting a detective to describe the events of a surveillance video that was later watched by the jury.Defendant argued the trial court erred by permitting a detective to describe the events of a surveillance video that was subsequently watched by the jury. However, the narration was not secondary evidence admitted to prove the content of the video, and was not inadmissible lay opinion testimony. The detective simply testified as to what she saw and did not provide an opinion.id: 27055
Updated 2/4/2024The trial court properly disallowed statements made by defendant to the psychiatrist to show a basis for the expert’s opinion. Defendant argued the trial court erred by sustaining the prosecutor’s objections to questions defense counsel posed to its mental health expert. The questions involved statements defendant made and were asked to show the basis for the expert’s opinion. However, the statements were hearsay and defendant did not invoke a hearsay exception. id: 27303
Updated 2/4/2024The court properly admitted an officer’s lay opinion that the substance on defendant’s pants looked like blood. The trial court did not err by allowing the police officer to testify that he thought the stains on defendant’s pants were blood. That was not a subject beyond common experience and was proper lay opinion testimony. id: 27842
Updated 2/4/2024The trial court did not err in allowing statistical evidence showing that most child molesters know the victims or that most victims failed to report within one year.The trial court in a child sex abuse case did not err in allowing an expert to present statistical evidence showing that 94 percent of child molesters had a relationship with the victim and that 74 percent of abused children had not reported it within one year. These are not the kind of statistics that convey a conclusion regarding the defendant’s guilt.id: 27677
Prosecutor’s comment during closing argument that he thought defendant was a murderer was based on evidence, and did not constitute improper vouching.During closing argument the prosecutor said “Carl Powell is a cold-blooded murderer. That’s what he is and that’s what I think he is.” The comment did not amount to improper vouching because it was made in passing while discussing what the evidence showed. id: 25868
Testimony of lead investigator’s belief in defendant’s guilt was a product of the defense strategy of showing the police prejudged the case. Defendant argued trial counsel rendered ineffective assistance by failing to object when the prosecution’s lead investigator expressed his opinion as to defendant’s guilt. However, the testimony was not improper in light of the defense strategy of trying to show that the police simply believed defendant was guilty and thus failed to investigate the case fully.id: 25793
Expert testimony relying on case-specific hearsay as the basis for an opinion that defendant was an SVP violated Sanchez.At defendant’s SVP trial, an expert relied on inadmissible hearsay to support his extensive testimony about defendant’s unrelated convictions and unproven allegations that he committed other acts of sexual violence. This testimony was inadmissible under People v. Sanchez (2016) 63 Cal.4th 665.id: 25004
The trial court properly allowed expert testimony on the issue of police training in the use of force.Defendant was convicted of resisting an officer in violation of Penal Code section 69. He argued that the trial court erred by allowing expert testimony on the issue of excessive force. However, the police practices expert’s testimony provided context on the question of excessive force and provided a basis for evaluating the officer’s handling techniques and choice of assistive tools. The expert did not give his opinion as to whether the police used excessive force.id: 24896
The trial court did not err by allowing expert testimony regarding the general practice of the defense bar in providing discovery to criminal defendants.The trial court did not err by permitting the testimony of a defense lawyer, who testified as an expert witness regarding the general practice of the defense bar in providing discovery information to clients in criminal cases. Contrary to defendant’s claim, the testimony was not based on speculation about what happened in this case, it supported a logical inference the jurors could draw from the evidence.id: 24801
Counsel’s failure to make Sanchez objection during MDO proceedings did not establish IAC where there was no showing that counsel lacked a legitimate tactical reason for not objecting.Defendant argued that his trial counsel rendered ineffective assistance of counsel by failing to raise a Sanchez objection (People v. Sanchez (2016) 63 Cal.4th 665) to case-specific hearsay expert testimony offered at his mentally disordered offender hearing. Although Sanchez applies in MDO proceedings to the extent it clarifies the admissibility of expert testimony under the Evidence Code, defendant failed to show that his attorney would have had no legitimate tactical reason for failing to make a Sanchez objection.id: 25359
Criminalist’s use of the Ident-A-Drug website to identify pills did not violate hearsay rule or the confrontation clause under Sanchez.Defendant was convicted of possessing a controlled substance for sale. The prosecution’s criminalist used the Ident-A-Drug website to presumptively identify the pills as controlled substances. Defendant argued the criminalist’s testimony regarding the website was inadmissible hearsay and violated the confrontation clause under People v. Sanchez (2016) 63 Cal.4th 665. However, the Ident-A-Drug website comes within the “published compilation” exception to the hearsay rule, and there was no confrontation-clause violation where the challenged hearsay was not testimonial.id: 25367
The trial court properly excluded the Abel test results used to show a lack of sexual interest in children, given the lack of acceptance of the test in the relevant scientific-community.Defendant charged with several child molest counts sought to present evidence showing he was not sexually deviant, which is permissible under People v. Stoll (1989) 49 Cal.3d 1136, 1140. He sought to use the “Abel Assessment Sexual Interest” test to prove he did not have a sexual interest in children. However, the Abel test results were properly excluded based on a lack of acceptance of such test results in the scientific community.id: 25264
The trial court did not abuse its discretion during the penalty phase by admitting a guard’s lay opinion that defendant was one of the five most manipulative inmates. Defendant argued that the deputy’s testimony that the defendant was among the “top five” inmates in manipulating a situation was impermissible opinion testimony. However, it tended to show the gravity of defendant’s conduct behind bars and the trial court had discretion to admit the lay opinion testimony during the penalty phase of defendant’s capital case.id: 25216
The trial court did not err by allowing an expert opinion that defendant was not a “blind mule.”Defendant argued the trial court erred when it allowed the prosecution’s expert (a Homeland Security special agent), to give an opinion that defendant was not a “blind mule” (unaware of the drugs in his car) when he entered the United States from Mexico. The expert relied on various factors showing defendant was not someone who lived in Mexico but worked in the United States, and described relevant facts about the type and location of the drugs found in the Mexican made car. Moreover, the defense expert relied on many of the same factors when describing the “typical” blind mule case.id: 24775
The trial court did not err by allowing the prosecution’s expert witness to criticize forensic psychiatry after the defense experts discussed defendant’s intellectual disability.The defense presented three experts to testify about defendant’s intellectual disability. The trial court did not thereafter err by allowing the prosecution’s psychiatrist to testify about the unreliability of the testing methods used by the defense experts. His criticism of forensic psychiatry and the opinions of the defense experts went to the weight of their opinions, not their admissibility.id: 24680
Gang expert’s opinions need not be based on facts that occurred at or near the time of the offenses.Defendant argued the trial court erred by admitting the gang expert’s opinion because the facts the expert used for support did not occur at or near the time of the charged offenses. Defendant cited the Kelly-Frye factors to challenge the expert’s methods but referred to no authority excluding nonscientific gang expert testimony based on these factors.id: 24378
An expert may opine that the offense presented in the hypothetical questions asked by the prosecutor was committed for the benefit of a street gang. Defendant argued that in response to the prosecutor’s hypothetical questions, the gang expert testified impermissibly about ultimate issues of fact constituting prejudicial legal conclusions. However, a gang expert presented with hypothetical facts may opine that the offense was committed for the benefit of the gang.id: 24379
A police officer qualified as an expert in drug sales need not also qualify as a medical marijuana expert where the defendant raises the compassionate use defense.A police officer need not qualify as a medical marijuana expert in order to render an opinion that marijuana being possessed is possessed for sales in cases where the defendant raises an affirmative defense under the Compassionate Use Act.id: 21504
The trial court did not err by excluding the testimony of a Chinese cultural expert suggesting that defendant reasonably believed the victim consented to the sex acts by sharing a glass of wine and loaning him various books.Defendant was charged with committing sex crimes against an acquaintance. The defense was consent or a reasonable and good faith belief in consent. The court did not err in excluding the opinion of an expert on Chinese culture suggesting defendant reasonably believed that by sharing a wine glass or books the victim agreed to an intimate encounter. Our society is not willing to tolerate a belief in consent that is based on the content of loaned books or the sharing of a glass of wine. The relevance of the proposed testimony was therefore minimal.id: 18654
Questions to defendant's pediatrician at the penalty phase regarding the impact of a trip to Canada he took as a youth did not call for expert medical opinions. The trial court did not err at the penalty phase in precluding the opinion of defendant's pediatrician regarding a trip to Canada defendant took as a child and the impact of that trip on defendant's academic development. Questions about the witnesses impressions and observations were not directed toward his medical expertise. Moreover, to the extent the questions called for lay opinion they were irrelevant since they would not have been helpful to understand his testimony about defendant's childhood difficulties.id: 19735
The trial court did not abuse its discretion by excluding certain out-of-court statements from the defense mental health expert’s testimony. Defendant argued the trial court abused its discretion in precluding the defense expert psychologist from disclosing statements by defendant that appear in the report of another psychologist, which the expert relied on in reaching his opinion that defendant has paranoid schizophrenia. However, there was no error as statements related to events at issue in the trial which created the possibility that the jury might consider them as independent proof of what happened, and the statements were self serving and unreliable. The trial court properly used its Evidence Code section 352 discretion to limit this “basis evidence.” id: 23898
The trial court did not err by allowing an expert to testify at the penalty phase about the probability of a baby pacifier fracturing where the defendant’s infant daughter may have died from such an event.The trial court did not err by allowing an expert to testify regarding the frequency with which rubber baby pacifiers can fracture. Testimony regarding what does and does not cause rubber to fracture is sufficiently beyond common experience to be admissible even if part of the testimony refers to matters of common knowledge. id: 23518
Admission of statements placed in STEP notices and FI cards, and testified to by the gang expert did not violate hearsay rule, section 352 or defendant’s confrontation clause rights under Crawford. Defendant argued the trial court erred by admitting evidence of statements contained in STEP notices, field identification cards and police reports to support the gang expert’s testimony. The materials considered here were not inadmissible hearsay and were the type normally considered by experts. And the statements were not unduly prejudicial under section 352 just because they were made to nontestifying officers. Finally, the evidence did not violate defendant’s confrontation clause rights under Crawford where it was admitted as a basis for the expert’s opinion and not for the truth.id: 23466
The evidence was insufficient to support the experts’ conclusions that he was cultivating marijuana under the MMPA, and that the amount he was to be paid did not include a profit. Defendant argued the trial court erred by refusing to allow his cannabis expert to give critical defense evidence including the fact that he was cultivating the marijuana under the MMPA, and the sum of $20,000 that he expected to be paid for the 100 plants, did not include an unlawful profit. However, the expert’s testimony was properly limited where he lacked sufficient evidence to render the opinions. The evidence did not show the money defendant expected to be paid would cover only his costs and expenses, and it did not support an opinion that the 100 plants defendant was cultivating would produce no more than necessary to supply the current needs of a collective comprised of six patients. id: 23701
The trial court did not err by allowing a former FBI agent to present expert testimony suggesting the victim was killed by one person who was close to her.The trial court did not err by allowing a former FBI agent to testify that the victim was not killed by a stranger, by more than one person, during a robbery or during a sexual assault. His analysis of the evidence could have assisted the jury in understanding that the victim’s murder was committed by a lone killer who was close to her. The testimony did not constitute inadmissible profile evidence.id: 23404
The trial court did not improperly exclude expert testimony challenging the reliability of breath-alcohol testing machines.The trial court did not err by excluding expert testimony challenging the reliability of breath alcohol testing machines. The excluded evidence included testimony that breath-testing machines are unreliable because expired breath contains only alcohol that has been absorbed from the upper airways and hence the machines fail to sample and analyze the concentration of alcohol contained in alveolar, deep lung air, and proposed testimony that breath testing machines are unreliable because other physiological factors may affect the transmission of alcohol from the bloodstream to the deep portions of the lungs and then through the exhalation process.id: 23391
The investigator’s testimony regarding the doctors’ medical opinions on cause of death was sufficiently reliable to be admitted at the preliminary hearing. In 2010, defendant was charged for a murder that took place in 1994. At the preliminary hearing, a homicide investigator with no specialized training testified about the forensic evidence and conveyed the expert opinions of two doctors who believed the victim died from nicotine poisoning. Defendant argued this testimony was unreliable and he should not have been bound over for trial. However, the expert opinion on cause of death was sufficiently reliable and the court did not err by allowing the investigator to present that evidence at the preliminary hearing. id: 23227
Defendant failed to object and therefore forfeited the right to challenge expert testimony that marijuana was possessed for sales.Defendant, who claimed that he legally possessed marijuana for medical purposes, challenged the expert’s testimony that he unlawfully purchased it for the purpose of sales. However, by failing to object at trial, he forfeited appellate review of whether the officer was qualified to testify as an expert. Moreover, the evidence was sufficient to support the conviction as he possessed several bags with identical amounts packaged for sale, he had no paraphernalia associated with personal use and he had a prior conviction of possession for sale.id: 23321
The trial court did not err in finding a witness qualified as an expert regarding a fingerprint device where she had read many books and was trained by Canadian law enforcement officials.The trial court did not abuse its discretion in finding the prosecution’s witness was an expert in analysis. While she was not a renowned expert on the use of the device in question (vacuum metal deposition device) she had read many books on the subject and was trained to use it by Canadian law enforcement officials.id: 23328
The trial court properly allowed the prosecution’s psychologist to testify as an expert in sexual homicides.The trial court did not err by ruling the prosecution’s psychologist could testify as an expert on sexual homicides but could not give an opinion that defendant fell into that group of killers. The witness was qualified because of his clinical experiences and published articles, and his opinion did not constitute a legal conclusion.id: 23327
The trial court did not err by allowing expert testimony regarding blackouts.During the defense penalty phase case, defendant testified he did not recall committing the murders. On rebuttal, the prosecution called Dr. Dietz to testify about blackouts. Defendant argued it was improper expert testimony because the jury could easily reach the same conclusions without any help from an expert. However, the testimony about what a blackout is, and what a person is aware of regarding an event he cannot later remember was beyond the common experience of the jury.id: 23312
The trial court did not err in readmitting the defense expert’s testimony correlating job loss to the commission of homicide.Defendant argued the trial court erred by readmitting the defense expert’s testimony correlating job loss to the commission of homicide. However, the court did not err by precluding reference to studies about the effects of job loss on homicide where it allowed the witness to express her opinion concerning how events in defendant’s workplace might have factored into his mental state on the day of the crimes. id: 23244
The prosecutor could properly cross-examine the defense expert about her mishandling tapes in a previous case to show her bias against the prosecution.The trial court did not err in allowing the prosecution to cross-examine the defense expert about her mishandling of interview tapes in a previous case. The evidence was relevant to establish a basis upon which the jury could find the witness’s failure to comply with the subpoena in this case was not the result of an innocuous misunderstanding, but rather an expression of antipathy towards the prosecution.id: 23243
The trial court did not err in excluding expert testimony on coerced confessions.The trial court did not err by excluding defendant’s proffered expert testimony on the issue of whether his confession was coerced. There was little evidence showing coercion and there was a good deal of corroborating evidence suggesting the confession and admissions were true. Under these facts, the evidence was highly speculative and properly excluded under Evidence Code section 352. Moreover, its exclusion did not violate defendant’s right to present a defense. id: 23275
CSAAS expert was qualified to testify that a sexual assault victim could have experienced an orgasm during non-consensual oral copulation. The trial court did not abuse its discretion in finding the prosecution’s child abuse sexual accommodation syndrome expert was qualified to testify that the victim could have experienced an orgasm during nonconsensual oral copulation. She had 25 years of experience working with sexual assault victims, mostly adolescent girls. She was a part-time professor and the clinical supervisor of a sexual assault trauma center and had been trained in human sexual behavior, with specific emphasis on the biology and physiology of sexual response.id: 23334
DNA analyst’s brief reference to a report prepared by another analyst did not violate defendant’s confrontation clause rights as it is the type of thing reasonably relied on by other DNA experts in forming their opinion.A “technical reviewer” of the DNA analysis done on bloodstains found on defendant’s clothing and a door testified that her job was to review al of the notes and data done in the analysis to ensure the results were accurate. Defendant claimed a confrontation clause violation due to his inability to question the person who did the original testing. However, there was no Crawford/Melendez-Diaz violation. The technical reviewer’s brief reference to the clothing/door analyst’s reports and her reliance on the raw data was proper because such items are reasonably relied on by experts in the field of DNA analysis in forming their opinions.id: 23079
A qualified mental health expert may rely on hearsay in a probation report to render an opinion on whether defendant is a MDO and the underlying offense involved force or violence.A qualified mental health expert may rely on reliable hearsay in a probation report in rendering an opinion on whether a defendant is a mentally disordered offender and whether the underlying offense involved force or violence.id: 23088
The trial court properly allowed the impeachment of the defense expert’s opinion with contrary statements made while testifying at the suppression hearing.Defendant argued the trial court erred by permitting the prosecutor to rebut the opinions of the defense expert witness, a psychologist who testified about defendant’s educational level and writing ability, by presenting the jury with statements defendant previously made at a pretrial suppression hearing, concerning whether he had the ability to express himself in writing. Allowing the statements to impeach the defense expert did not violate James v. Illinois (1990) 49. U.S. 307, because when a defendant’s testimony at a suppression hearing is contrary to a defense expert’s opinion that was partly based on his discussions with defendant, the rule established in James does not apply.id: 23016
SVP experts did not invade the jury’s province as they used statutory criteria to frame their opinions that defendant was “likely” to reoffend.Defendant argued that the trial court prejudicially erred at his sexually violent predator trial by permitting the prosecution’s expert to testify that he was “likely” to engage in “predatory” sexually violent offenses in the future because these were legal issues and the expert’s testimony invaded the jury’s province. However, the experts’ properly utilized statutory criteria to frame their opinions that they did not cross the line from testifying about bases for their opinion to advocating for a particular outcome.id: 22982
A sheriff’s department weapons trainer could testify a person under stress might mistakenly perceive the direction of gunfire. The trial court did not err by admitting the expert testimony of a firearms trainer at the sheriff’s department that a person under stress might mistakenly identify the direction from which a gun was fired. id: 22596
The forensic pathologist was properly allowed to give an opinion as to whether the victim had been raped before or after the killing.The trial court did not err by permitting the coroner who conducted the autopsy to give an opinion on whether the victim was raped before death, as opposed to later. He had extensive experience in rape murder cases and no further expertise was required. The evidence, while disturbing, was the clinical conclusion of the medical expert, and was not the type of evidence uniquely designed to evoke an emotional response for purposes of Evidence Code section 352.id: 22707
While some of an MDO expert’s testimony referred to inadmissible hearsay that was beyond the scope of admissible expert opinion, facts taken from a probation report admitted without objection showed defendant met the criteria.Defendant argued there was insufficient evidence to support the trial court’s finding that he was a mentally disordered offender under Penal Code section 2962 because the prosecution relied on inadmissible hearsay under the guise of expert opinion testimony. However, absent an objection, the court could properly rely on the expert’s response that defendant had been convicted of an arson of an inhabited structure. The additional fact needed to satisfy section 2962, that the crime posed a serious risk of harm to others, was found in the probation report showing defendant’s brother suffered from smoke inhalation.id: 22667
While some of an MDO expert’s testimony referred to inadmissible hearsay that was beyond the scope of admissible expert opinion, facts taken from a probation report admitted without objection showed defendant met the criteria.Defendant argued there was insufficient evidence to support the trial court’s finding that he was a mentally disordered offender under Penal Code section 2962 because the prosecution relied on inadmissible hearsay under the guise of expert opinion testimony. However, absent an objection, the court could properly rely on the expert’s response that defendant had been convicted of an arson of an inhabited structure. The additional fact needed to satisfy section 2962, that the crime posed a serious risk of harm to others, was found in the probation report showing defendant’s brother suffered from smoke inhalation.id: 22666
The trial court did not err by allowing an expert in fingerprint identification to testify as an expert on the durability of fingerprints.Defendant argued the trial court abused its discretion by allowing a forensic identification deputy to testify about the durability of fingerprints. However, the witness was trained in fingerprint evidence including the circumstances under which they may be lifted and the ways they may become contaminated and unusable. The court did nto err in allowing the expert to testify about the durability of fingerprints. id: 22617
The trial court did not abuse its discretion in ruling the jurors at the penalty retrial did not need expert testimony on the issue of whether defendant’s abusive childhood contributed to adult criminality.The trial court did not abuse its discretion at the second penalty retrial by excluding expert opinion testimony on the ground that the jury did not need the doctor’s testimony to assist in determining whether defendant’s childhood experiences could have affected his behavior as an adult. The jurors could rely on their common sense to consider whether defendant’s abusive childhood could have contributed to later criminal behavior.id: 22757
The trial court did not err by excluding expert testimony that the city’s credit card resolution did not contemplate criminality.Defendants were city officials convicted of misusing public funds under section 424. The trial court properly excluded expert testimony from the former city official who would have said the credit card resolution did not “contemplate criminality” because that testimony could have invaded the province of the trial court in instructing the jury on the applicable law.id: 22822
The trial court did not err by allowing hypothetical questions of the gang expert that closely tracked the evidence in the case. An expert witness testified that the charged crime was gang related. Defendant argued (and the Court of Appeal agreed) that the trial court erred in permitting the expert to respond to hypothetical questions the prosecutor asked because the questions closely tracked the evidence in a manner that was only thinly disguised. There was no error as it is required, not prohibited, that the hypothetical questions be based on the evidence. The questioner is not required to disguise the fact that the questions were based on the evidence.id: 22467
The trial court did not err in permitting expert testimony on the reactions of a developmentally disabled person to sexual advances.The trial court did not abuse its discretion in allowing expert testimony and opinion as to whether there were reasons why a person with a developmental disability, as described in the evidence before the jury, would not seek assistance from third parties when faced with a perceived danger or threat from a person’s sexual advances. That information was beyond the range of general knowledge of the average juror or the opinion of an expert could at least be helpful in evaluating victim testimony. id: 22072
The trial court did not err in finding the gang expert could testify on direct exam about the out-of-court statements he relied on in forming certain opinions. Defendant challenged the trial court's determination that the gang expert could testify on direct examination about the out-of-court statements he relied on in forming certain opinions. The trial court ruled that such statements did not come in for their truth, but only to assist the jury in evaluating the expert's opinions. The trial court's opinion was supported by People v. Thomas (2005) 130 Cal.App.4th 1202, which relied on relevant California Supreme Court precedent (People v. Gardeley (1996) 14 Cal.4th 605) and was binding. However, the court disagreed with Thomas and proposed an approach that preserved the goals of Gardeley while recognizing the reality of how jurors treat out-of-court statements admitted as basis evidence.id: 21994
The gang expert's testimony regarding the shooting of a rival gang member who was not the original target, and motive to shoot a police officer did not exceed the scope of his expertise. The trial court did not err by qualifying a San Francisco police inspector as a gang expert. Defendant conceded the officer was qualified to testify as to Bayview gang "culture" but argued his testimony exceeded the scope of his expertise. However, the witness's expertise was adequate to permit him to opine that a gang member intending to shoot a particular gang rival would shoot a different member of the rival gang if the intended victim was not present, and to support his opinion regarding a gang member's motive to shoot a police officer.id: 21992
The trial court did not err at the penalty phase by prohibiting the defense witness, a social worker, from testifying about the genetic basis for defendant’s substance abuse problems.The trial court did not err at the penalty phase of defendant’s capital trial by finding the defense expert was not competent to testify about a genetic basis for defendant’s drug and alcohol problems. The witness was trained as a social worker to collect information concerning family substance abuse, but he was not an expert in genetics and was not qualified to testify about the genetic basis of defendant’s family history.id: 22277
The trial court did not err by allowing the prosecution’s expert to refute with her own undocumented experiment results, the defense expert’s claim that infusing defendant’s body with saline affected the blood analysis for drugs and alcohol. The defendant was charged with four counts of capital murder after she shot her four sons, and then shot herself in the stomach, ultimately surviving. She argued at trial that the killings were not premeditated in light of her heavy ingestion of alcohol and Valium. She claimed the testing of these substances gave a low reading because she was tested after receiving many saline infusions for her own wound. On appeal, she claimed the trial court erred by permitting the prosecution’s expert to refute this claim based upon informal experiments the expert had conducted years earlier on her own. However, the expert opinion was founded on information on which an expert may reasonably rely, and the fact that a similar conclusion had been omitted from a new version of a medical textbook did not render her testimony inadmissible.id: 22545
Police investigator was properly permitted to give expert testimony on controlling arrestees as he interpreted the defendant’s actions on a video recording.Defendant was a police officer charged with assault. A police investigator who had taken a compelled statement from defendant was called at trial to give an opinion as to whether the videos showed defendant had control of the arrestee during the arrest. The defense argued the investigator’s opinions were inadmissible as expert testimony. He argued that because the witness purported to base his opinion on the video recordings, his testimony was not beyond the common experience of the jurors. However, the witness did not just describe the video recording images, he interpreted them as an experienced police officer. Moreover, the witness did not claim to be an expert in use-of-force, and limited his testimony to techniques for controlling arrestees.id: 21439
CSAAS testimony was admissible to explain why the child molest victim retracted her initial allegations at trial.The trial court did not err by admitting evidence of child sexual abuse accommodation syndrome to explain why children may retract the initial allegations at trial. CSAAS testimony is admissible to rehabilitate a molest victim’s credibility, and the record was insufficient to make a meaningful challenge to the law.id: 21444
The trial court did not err in allowing defendant’s mental health expert to be impeached with the reports of the court appointed competency experts. Defendant presented expert testimony in support of a mental health defense at the guilt phase. The trial court did not err in allowing the prosecution to cross-examine the expert with the evidence on which he based his opinion, including the hospital records and reports of the court appointed competency experts.id: 21530
The trial court did not abuse its discretion by allowing an investigator to give expert testimony that child molest victims often forget details.The trial court did not err by permitting an investigator with the sheriff's department to testify as an expert witness that victims of long term child molestation often forget details or have trouble distinguishing the different incidents. Assuming the court erred by allowing the testimony, the error was harmless in light of the strong evidence of defendant's guilt. id: 21645
The trial court did not err by excluding speculative expert testimony that the deaths could have been caused by carbon monoxide poisoning.The trial court did not err by excluding a defense expert from testifying that carbon monoxide poisoning from a water heater attached to the house could have caused the deaths. The evidence was speculative, based on unreliable hearsay and lacked foundation.id: 21217
The trial court did not err by excluding expert testimony on alcoholic blackouts.Defendant was convicted of kidnapping for rape. He argued the trial court erred by excluding expert testimony on alcoholic blackouts. However, the record supported the court’s conclusion that the testimony would have little probative value since it was mere speculation that the victim suffered a blackout while in defendant’s presence. The evidence supported the additional conclusion that such testimony would confuse the jurors.id: 21216
The trial court did not err by excluding expert testimony on how an inmate can gather evidence to concoct a confession.The trial court did not err in denying the defense request to call a private investigator to testify as an expert on how an inmate can gather information to concoct a false confession by another inmate. There was insufficient foundation for the testimony absent evidence that De Soto was a repeat inmate informant or of evidence contradicting his testimony that defendant was the sole source of his information. id: 20975
The trial court properly allowed the prosecution expert to describe paraphilia and any error in allowing the conclusion that defendant’s actions were consistent with the disorder was harmless.Defendant argued the trial court erred in permitting the prosecution to introduce expert testimony concerning paraphilia as an explanation of his motive to both the present case involving the sexual assault and murder of a 12 year old girl , and his prior sex crimes. The court properly allowed the expert to describe the disorder. Any error in allowing the expert to conclude defendant’s actions were “consistent” with the disorder was harmless where the evidence was so strong that the jury could easily have reached the same conclusion.id: 21010
The juvenile court did not abuse its discretion in allowing the police officer to give expert testimony regarding the use of stun guns.The minor argued the juvenile court abused its discretion in admitting expert testimony regarding the stun gun used by the minor. However, the minor never objected below that the police officer was not qualified to offer testimony on the subject. Assuming the issue was not forfeited, the officer’s testimony regarding his experience with stun guns was beyond common experience and helpful to the trier of fact, as required by Evidence Code section 801. His testimony that he had seen injuries caused by stun guns was not expert medical testimony.id: 20994
The prosecutor did not commit misconduct at the penalty phase by cross-examining the defense expert about disciplinary violations reflected in defendant’s CYA and probation records.Defendant argued the prosecutor committed misconduct at the penalty phase by cross-examining the defense mental health expert about the disciplinary violations reflected in defendant’s CYA and probation records. However, the cross-examination was not conducted to establish evidence in aggravation, but to impeach the expert’s opinion that, because of ADD, defendant committed the crimes impulsively.id: 20933
The trial court did not err in allowing expert testimony on defendant’s White supremacist and anti-semitic beliefs based on materials found in his house where he killed a Vietnamese man and made racist comments at the time. Defendant was convicted of the murder of a Vietnamese victim. He argued the trial court erred by allowing a police expert to testify that material found in defendant’s bedroom referred to White supremacist organizations and espoused White supremacist beliefs. However, the court did not err in refusing to limit the evidence which was relevant to defendant’s state of mind at the time of the killing, and whether he killed the victim because of his race for purposes of the hate-murder special circumstance. id: 20589
The juvenile court did not improperly admit expert testimony regarding the common usage of bicycle footrests as “metal knuckles”.The juvenile court did not abuse it discretion in permitting the police officer’s expert testimony regarding the common usage of bicycle footrests as metal knuckles since the testimony was minimally probative of the minor’s intent. Moreover, the officer never testified to what he believed the minor’s mental state to be at the time of his arrest, but instead his testimony was limited to common practices of which he was aware based on his experience.id: 20590
The trial court did not err by allowing impeachment of the defense psychiatrist with incidents that were relevant to the expert’s opinion that defendant did not have the character of a murderer.Defendant argued that trial court permitted improper impeachment of the defense psychiatrist and that the prosecutor’s questions were an improper attempt to offer specific instances of irrelevant and inadmissible character evidence on a specific occasion. However, the cross-examination was proper as the incidents mentioned were all relevant to the expert’s opinion that defendant’s character was inconsistent with that of a murderer.id: 20744
The trial court did not err in allowing a police officer to testify that a witness had previously provided critical information.Defendant argued that the police officer’s testimony that a key witness had provided critical information in previous murder cases was an inadmissible opinion about the credibility of a witness. Assuming the characterization of the information as “critical” constituted opinion testimony, the detective was entitled, as a professional who had overseen the investigations, to give such an opinion.id: 20447
The methodology for assessing the statistical significance of a “cold hit” from a DNA database does not require proof of general scientific acceptance. Defendant was arrested in 2002 for a 1976 murder after a “cold hit” from a DNA database. Contrary to defendant’s claim, the use of the product rule to calculate match probability in a cold hit DNA case is not a new scientific technique subject to the Kelly test. Moreover, although the product rule is not the only available method of statistical analysis in a cold hit case, it is relevant and thus admissible.id: 20408
Detective properly testified as a lay witness regarding the significance of certain markings on the shotgun shell. Defendant argued the shotgun shell was inadmissible because the detective did not testify as a ballistics expert as to the significance of strike marks on the shell, indicating a failed attempt to fire the shell from a shotgun. However, the detective properly testified as a lay witness and the subject of his opinion – the significance of the marks on the shell primer was not so far beyond the common experience that expert testimony was required.id: 20412
The trial court did not err in excluding the penalty phase testimony of a criminologist who could not offer expert opinion on the psychological impact of defendant’s upbringing.The court did not err in excluding the penalty phase investigator, a criminologist, who did extensive research on defendant’s background and was prepared to “synthesize” information already presented through other witnesses. However, the court found he was not an expert, but rather a penalty phase investigator whose role was to analyze records and information collected by other witnesses. He was not qualified to offer an expert opinion as to the psychological impact of defendant’s upbringing on his current behavior or how he would adjust to life in prison.id: 20330
Officer's testimony sufficed to prove the shotgun shell was live ammunition under section 12101, subd.(b)(1).The minor was found to have possessed a concealable firearm within the meaning of Penal Code section 12101, subd.(a)(1) and live ammunition in violation of section 12101, subd.(b)(1). He argued the evidence did not support the allegation that the shotgun shell taken from the gun was "live." However, the police officer's testimony was direct evidence that the round was live and supported the conviction.id: 20202
Court did not err in admitting expert testimony that the shooting of a person by a gang member after asking where he was from, was gang related.The prosecutor asked the gang expert why someone would ask a person where they were from and then shoot them. The expert opined that such behavior by a known gang member was likely done for gang related purposes. The trial court did not err in admitting the testimony.id: 15030
The gang expert's opinion that witnesses may be intimidated was not inadmissible where he did not describe a particular witness, and the fact that gang members sometimes lie, did not discredit his testimony.Defendant argued the gang expert's testimony was inadmissible because he testified the witnesses were intimidated, not that people may be intimidated by gang members. However, the testimony made the evidence probative not inadmissible. Moreover, the expert's testimony was not an impermissible opinion as to the credibility of a certain witness because he was not asked about and did not testify about any particular witness. Finally, the expert's statement that gang members sometimes lie did not disqualify him for an opinion based on unreliable information. A gang expert's opinion is usually based on several sources, which in sum may be reliable.id: 19111
An officer may draw an opinion as to the defendant's intoxication based upon his own experience with the horizontal gaze nystagmus test.An officer with sufficient experience may testify, based on his or her own experience with the relationship between the horizontal gaze mystagmus test and alcohol intoxication, to an opinion that a subject was or was not under the influence.id: 10555
Possession for sale conviction was reversed due to lack of substantial evidence that the officer/expert had sufficient expertise with the lawful use of marijuana.Defendant, who was entitled to consume marijuana under the Compassionate Use Act, was convicted of possessing his marijuana for sale based largely on the opinion of the arresting officer. However, the conviction was reversed as there was no substantial evidence that the officer had any expertise in differentiating citizens who possess marijuana lawfully for their own consumption from those who possess it unlawfully with the intent to sell.id: 20021
The trial court did not err in finding the blood spatter expert was properly qualified or in deferring its ruling on the matter until midtrial. The trial court did not abuse its discretion in finding the prosecution's blood spatter expert was properly qualified due
to his educational background and work experience. No Evidence Code section 402 hearing was required. Moreover, the trial court did not err in deferring until midtrial any ruling on the
admissibility of the expert testimony.id: 19767
The trial court did not err in allowing an FBI expert to testify as to whether all crimes were committed by one person.The trial court did not abuse its discretion in allowing an FBI agent to testify as an expert on the issue of whether all of the charged crimes were committed by the same person. The matter was beyond the common experience of jurors, at least to the point that an expert opinion would assist the jury. Moreover, the expert did not testify defendant was guilty, tell the jury who to believe or direct the jury to a specific conclusion
on any element of a charged crime.id: 19601
Allowing expert opinion on a victim's mental capacity which was based in part on videotaped interviews did not violate Crawford.The trial court erred in precluding the testimony of its expert on the ground that her opinions were based in part on the testimonial interviews of the victim. Crawford does not suggest the confrontation clause is implicated by the admission of hearsay for nonhearsay purposes. To the extent the expert opinion regarding the victim's mental competency was based on the videotaped interviews, the confrontation clause did
not prevent her from rendering an opinion and stating the sources of information on which she relied in reaching it.id: 19501
The trial court did not err by restricting expert testimony regarding statements defendant made to the psychologist about the crime.The trial court did not err by prohibiting the defense psychologist from recounting defendant's statements regarding his killing of Joey. Allowing the statements would have effectively permitted the defendant to testify without being subject to cross-examination. Any error was harmless where ample evidence of defendant's statements was presented by both parties.id: 19459
The trial court did not err by allowing expert testimony to explain why a prostitute might change her testimony out of fear or embarrassment because of conduct or loyalty to a pimp.Dr. Lee had a Ph.D in social psychology, a law degree and had done extensive research and written numerous articles on prostitution since 1973. He was therefore qualified to testify as an expert on the culture of prostitution and pimping. Moreover, the court did not err in allowing expert testimony as to the reasons a prostitute might change her testimony out of fear or embarrassment because of conduct or loyalty to a pimp. Finally, the testimony did not amount to improper "profiling" evidence, but rather, related to the experiences of young girls drawn into prostitution by pimps.id: 19373
Court was not required to instruct on limited use of statements to a psychiatrist where the expert testified for the defense at the penalty phase.Defendant argued the trial court had a sua sponte duty to instruct the jury that defendant's statements made during a
mental health exam could only be considered to show the information upon which the expert based his or her opinion. However, such an instruction is appropriate where the expert is
appointed and testifies at the guilt phase, not here where the expert testified for the defense at the penalty phase.id: 19204
Erroneous factual assumptions of SVP experts should have been addressed through cross-examination and did not render their testimony inadmissible.Defendant argued the testimony of the expert witnesses at his SVP trial was inadmissible because their conclusions that he used force in the 1998 incident erroneously assumed defendant used force in holding the victim's pants down. However, any erroneous factual assumptions by the experts should have been addressed through cross-examination and by showing there was no evidence to support their conclusions.id: 18905
The trial court did not err in allowing an experienced pathologist to give an opinion concerning the probable positions of the victims and the shooter.A pathologist provided an opinion that the victims died of gunshot wounds to the head from close range, and he described the trajectory of the bullets. Over defense objection he was also permitted to testify concerning the probable relative positions of the victims and the shooter. Defense counsel argued such testimony could only be given by a qualified crime scene reconstructionist. However, an experienced pathologist who possessed extensive familiarity with gunshot wounds was qualified to give an opinion on the subject. , ____ Cal.4th ____, ____ Cal.Rptr.3d ____, 2005 D.A.R. 14438 (2005) December 15, 2005. <$!People v. Robinson, ____ Cal.4th ____, ____ Cal.Rptr.3d ____, 2005 D.A.R. 14438 (2005) December 15, 2005.>id: 18859
The trial court did not err by failing to instruct the jury to consider the facts upon which the expert's opinion was based.The trial court did not err in telling the jury that, in assessing the testimony of an expert, it should consider the expert's opinion with the reasons given for it, without further instructing the jury to consider the facts on which the opinion was based.id: 18702
The prosecutor did not err by eliciting testimony from a witness that defendant was in a "maniacin" mood on the night of the murder.Defendant argued the prosecutor committed misconduct by eliciting testimony that defendant was in a "maniacin" mood on the night of the murder. However, the testimony was not improper lay opinion evidence. The testimony defined the witness's use of the term which needed explanation because it lacked a commonly understood meaning. Her opinion was admissible because it was based on her perceptions and helped to better understand her testimony. Moreover, contrary to defendant's claim, the jury would not have understood the statement defining the term "maniacin" as referring to defendant's affiliation with a gang called the "Sacramaniacs."id: 18684
Mental health experts properly relied on the probation reports as the basis of their opinions that the evading officer offense involved force or violence for MDO purposes.Defendant argued he did not qualify as a mentally disordered offender because his underlying offense (evading an officer under Vehicle Code section 2800.2) was not a crime of force or violence. Contrary to defendant's claim, there was no error in allowing the mental health experts to describe the probation report in stating the basis for their opinions on the force or violence criterion.id: 18459
The trial court did not err in excluding defendant's cult expert since the witness was not a mental health expert and was not qualified to give an opinion on whether defendant had an illness that would preclude him from forming intent for murder.Defendant argued the trial court erred in refusing to admit, at the guilt phase, the testimony of a former detective who specialized in the study of cults. Defendant sought to show that because of mind control over him by a confederate, he was unable to form the required mental state for first degree murder. Here, the proposed witness was not a mental health expert and was not qualified to render an opinion on whether defendant had the mental state requisite for first degree murder.id: 18412
The court did not err in allowing Dr. Oshrin to testify as a prosecution rebuttal witness even though the defense decided not to call him since other defense witnesses testified they relied in part on Dr. Oshrin's report.During the penalty phase, the defense called two psychologists who testified that in preparing for the case they read the report of Dr. Oshrin - who interviewed defendant and prepared the report, but was not called by the defense at trial. Defendant argued the trial court erred by allowing the prosecution to call Dr. Oshrin as a rebuttal witness. However, defendant waived all privileges regarding all matters the psychologists considered or on which they relied, including Dr. Oshrin's report. Because defendant waived these privileges regarding Dr. Oshrin's report, the prosecutor was free to call him as a rebuttal witness and question him about the report.id: 18281
The trial court did not err in limiting the proposed expert testimony on "spillover" rage.The trial court did not abuse its discretion in excluding some of defendant's proposed expert testimony on the concept of "spillover rage." The doctor was permitted to testify about the spillover concept in the abstract, and how it might relate to defendant's conduct on the day of the murders. The portions of the testimony that were excluded were narrow and fell directly within the prohibitions of Penal Code sections 28 and 29.id: 18241
Trial court did not abuse its discretion by excluding expert testimony relating nontestifying experts' opinions, even if those opinions were relied upon by the defense expert in forming his opinionDefendant argued the trial court unduly limited his expert's testimony during the sanity phase. He claimed the court erred in precluding his testifying expert from testifying as to the opinions of the nontestifying doctors who examined defendant closer to the time of the murder. While the court had discretion to admit the testimony, it not abuse its discretion by excluding the hearsay evidence as it is well-established that it generally impermissible for a testifying expert to recount the details of another physician's report or opinion.id: 18106
Expert testimony on the behavior of domestic violence victims after only a single violent incident was admissible under section 801.At defendant's domestic violence trial the prosecution offered testimony from an expert witness to explain that domestic violence victims often later deny or minimize the assailant's conduct. Defendant argued the testimony did not fall within the scope of Evidence Code section 1107 which authorizes expert testimony on battered women's syndrome since the prosecution failed to show the defendant battered the victim on more than one occasion. The court did not reach the issue of whether the evidence was admissible under section 1107. Instead, the court found it was admissible under section 801, because it would assist the trier of fact in evaluating the credibility of the victim's trial testimony and earlier statements to police by providing relevant information about the tendency of domestic violence victims to later recant or minimize their description of that violence.id: 18017
Since the addiction expert never examined defendant, the court did not err in requiring the defense to use hypothetical questions.Defendant argued the trial court erred by precluding defense counsel from asking his drug addiction expert how defendant's use and abuse of drugs affected him in the days before the killing. However, the court properly ruled that since the witness never saw or examined defendant, the questioning should be raised in the form of a hypothetical.id: 17875
Trial court did not err by excluding expert testimony regarding the "usual" reactions of trauma victims.Defendant was convicted of several sex offenses against minors. He argued the trial court erred in excluding testimony by a defense expert witness regarding the "usual" reactions of trauma victims, which was offered to show the demeanor of one of the minors was inconsistent with having been molested. However, the proposed testimony about the "usual" demeanor of trauma victims was not relevant to correct any misconception about the behavior of molested children. If anything, it would have reinforced the common belief that traumatized victims are emotional or crying when describing the event. Moreover, the testimony would not rebut that of the prosecution expert who described the child sexual abuse accommodation syndrome since the witness said nothing about the demeanor one would expect of the child molest victim describing the incident.id: 17853
Court did not err in prohibiting defense expert from testifying as to the opinion of the previous defense expert.The defense expert died prior to trial and defendant thereafter retained another expert. The ultimate conclusion of the first expert was slightly more favorable to defendant. The trial court did not abuse its discretion in prohibiting the expert at trial from testifying as to the opinion of the first expert. The proffered evidence would have confused the jury by introducing conflicting opinions. Moreover, the first expert was not available for cross-examination.id: 17737
Court did not err in allowing a non-expert officer to testify the tread on defendant's shoe was similar to the prints in the dirt.The trial court properly allowed a non-expert police officer to testify that shoeprints found in the dirt at the scene of a crime were "similar" to the pattern on the soles of defendant's shoes.id: 17614
Expert testimony on battered women's syndrome is admissible when there is no evidence the alleged victim was previously abused.It is proper to admit expert testimony on the battered women's syndrome when there is no evidence the alleged victim was abused prior to the charged incident. As a result, BWS evidence may be admissible to offer an explanation regarding an explanation regarding why an ostensibly first-time victim of domestic violence recants testimony.id: 17226
Court did not err in allowing evidence of the computerized fingerprint matching program.After an Evidence Code section 402 hearing the trial court allowed the prosecutor to present testimony from an officer regarding the LA Police Department's use of a computerized database for fingerprint matching (the CAL-ID system), that produced a list of candidates, which included defendant, whose fingerprints were similar to those found at the crime scene. Contrary to defendant's claim, this was not the type of evidence that might evoke prejudice by making it appear as though defendant was the subject of an "unimpeachable" computerized decision. Moreover, the CAL-ID system was not subject to the Kelly analysis requiring a showing of acceptance within the scientific community.id: 16847
Pathologist could testify in redirect that the killing may have been premeditated after stating on cross-examination that it could have been a product of rage.Defendant argued the trial court erred when it permitted the forensic pathologist who performed the autopsy to testify on redirect examination that the killing was premeditated. However, once the defense elicited the opinion on cross-examination that the killing might have been done in a rage, the prosecution was entitled to elicit on redirect the further opinion that it might also have been methodical.id: 16818
A lay person can testify to an opinion based on a comparison of a shoe and a shoe print.The police officer's lay opinion that the sole of defendant's shoe appeared the same as the shoe print on the counter was admissible under Evidence Code section 800.id: 16029
Battered woman syndrome evidence is relevant when there is no evidence of prior abuse.At defendant's trial for assaulting his wife, he argued that the testimony of a domestic abuse counselor, concerning battered woman syndrome, was irrelevant because there was no evidence of prior incidents of abuse. However, there is nothing in Evidence Code section 1107 to suggest that the Legislature intended that a batterer get one free episode of domestic violence before admission of evidence to explain why a victim of domestic violence may make inconsistent statements about what occurred and why such a victim may return to the perpetrator.id: 16030
Battered Woman Syndrome testimony was properly admitted even though the victim was not recanting at trial.The prosecution offered expert testimony on Battered Woman Syndrome because they correctly anticipated the defense attack on the victim's credibility based on her written recantation of the 1993 incident and her decision to reunite with defendant after he had served time for the 1993 attack. Contrary to the defendant's claim, the court properly admitted the evidence even though the victim was not recanting at trial. The syndrome testimony was probative regarding both the victim's recantation of a prior incident and her decision to resume the relationship with the defendant before the charged incident.id: 16031
Battered women's syndrome testimony was admissible to explain the victim's recantation of her earlier allegations against defendant.Evidence Code section 1107 provides for the admission of expert testimony on battered women's syndrome in certain circumstances. In the instant case, the victim reconciled with defendant and recanted her original allegations at trial. The expert testimony on battered women's syndrome was therefore relevant and admissible to explain or offer a motive for the victim's recantation and thereby reconcile inconsistencies in her testimony.id: 16032
Court did not err in permitting radiologist's testimony on the apparent size of the bullets as they appeared in the x-ray photo.Defendant argued the trial court erred in permitting testimony by the radiologist on the subject of ballistics - a topic on which he was not an expert. However, the doctor simply testified the x-rays showed the two bullets appeared to be the same "caliber", by which he could have meant size. Defendant did not object or ask for clarification. Moreover, the doctor did not conduct an experiment that was subject to the <i>Kelly</i> requirements. The x-ray procedure simply gave the radiologist an opportunity to describe the physical effect of the shooting that the jury could not discern without expert help.id: 16033
Court did not violate Penal Code section 29 by allowing doctors to testify that defendant was malingering.Medical experts' testimony to establish that defendant falsified his symptoms does not violate Penal Code section 29, which prohibits an expert from testifying whether a defendant has the required mental state to commit the crime charged.id: 16034
Prosecution expert's testimony attacking psychiatric opinions in a generic sense was not improper.The prosecutor's psychiatric expert testified in rebuttal that mental health experts are no more qualified than lay persons to determine a defendant's mental state at the time of a crime. Defendant argued the testimony deprived him of the constitutional right to psychiatric assistance in preparing his defense, denied him the right to have the jury consider his defense, and usurped the court's role in determining the qualifications of expert witnesses and the reliability of scientific methods. However, the testimony was neither improper nor prejudicial because it did not suggest psychiatrists should be barred from the courtroom. The testimony addressed the weight rather than admissibility of the opinions of the defense experts.id: 16037
The trial court did not abuse its discretion in permitting expert opinion, based in large part on hearsay, that members of different gangs killed the victim for the benefit of the gang.Defendant and nine others were charged with murder, and a street gang enhancement under Penal code section 186.22 was alleged. The trial court did not abuse its discretion in permitting a police officer to give an expert opinion that the charged defendants who represented seven different Norteno gangs, could have been acting for the benefit of the gang. Such opinion was not tantamount to a true finding on the enhancement where other elements to the allegation had to be proved. Moreover, the court did not abuse its discretion in permitting the officer to relate the large amount of detail upon which he relied including portions of letters written to or sent by gang members.id: 16038
The trial court properly excluded BWS testimony regarding defendant's state of mind at the time of the killing.Defendant was convicted of the murder of her boyfriend after years of abuse. The trial court correctly ruled defendant's expert could discuss the trauma associated with battered woman's syndrome, but expert testimony regarding defendant's state of mind at the time of the crime was inadmissible. Moreover, the prosecutor's expert improperly stated his opinion concerning defendant's state of mind at the time of the crime. However, the prosecutor's failure to prevent the testimony did not deny defendant a fair trial, the court immediately admonished the jury to disregard the testimony, and defendant's ordinary objection to the testimony may not have preserved the issue for appeal where he received a favorable ruling.id: 16039
The trial court properly excluded the testimony of a proposed expert witness regarding self-defense in the Hispanic culture.Defendant was convicted of second degree murder after stabbing a reckless driver in an incident which began with "road rage." Defense counsel attempted to introduce for purposes of self-defense expert testimony on the sociology of poverty, and the role of honor, paternalism, and street fighters in the Hispanic culture. However, the court properly denied the evidence which was irrelevant to 1) whether defendant actually believed he was in imminent danger of death or great bodily injury; and 2) whether such a belief was objectively reasonable.id: 16040
Trial court did not abuse its discretion in excluding defense expert on topic of false confessions where there was no evidence police used improper tactics.The trial court did not abuse its discretion in excluding an expert witness who was prepared to testify on the topic of false confessions and tactics used by police to elicit such confessions. There was no evidence that police engaged in improper tactics by wearing down the defendant until he confessed. Moreover, the testimony was unnecessary since defendant testified he falsely confessed because of the officer's promise that he would serve no more than one year in custody.id: 15661
Court did not err in excluding the defense expert from the courtroom despite the claim that she was needed to assess the victim's story and help frame cross-examination.Defendant argued that it was necessary to have his expert witness (a psychologist) present in the courtroom during the alleged child molest victim's testimony to personally assess the victim's story and to help frame the cross-examination. However, the trial court did not abuse its discretion in excluding the witness from the courtroom. There is no authority that requires the presence of an expert to assess the demeanor of a witness or assist in cross-examination. Moreover, the doctor could have assisted with the cross-examination using the witness' testimony from the preliminary hearing.id: 15033
Court did not prejudicially err in allowing a detective to testify that defendant intended to steal inside the house since the witness was thoroughly cross-examined and the evidence of guilt was substantial.Defendant argued the court erred by allowing the detective to testify that defendant was inside the house with the intent to commit a theft. However, defendant did not specifically object at trial that the testimony was improper expert testimony. Moreover, the detective did not express an opinion on guilt, and admitted during cross-examination that she did not know what defendant was thinking. Any error was harmless in light of the overwhelming evidence of guilt.id: 15034
Trial court properly allowed the expert testimony of an agent regarding the significance of various activities and the role of each defendant in the hierarchy of a Columbian cocaine distribution cell.The trial court did not err in admitting the testimony of a California Department of Justice's Bureau of Narcotics Enforcement agent regarding the significance of various activities and the role of each defendant in the hierarchy of a Columbian cocaine distribution cell. The subject matter of the testimony was sufficiently beyond the common expertise of the trier of fact to render expert testimony not only helpful but necessary for an understanding of the meaning and impact of the various actions.id: 13041
Allowing general testimony concerning child sexual abuse accommodation syndrome did not require reversal.Trial court did not commit reversible error in allowing expert testimony concerning the child sexual abuse accommodation syndrome to explain why abused children sometimes behave in ways inconsistent with their having been abused. The court invited defense counsel to draft an appropriate limiting instruction but no such instruction was submitted.id: 13006
Allowing psychiatrists to testify as to their views of the death penalty was proper where such testimony was offered for the limited purpose of establishing bias.Defendant argued the court erred in allowing questions to the psychiatric experts regarding the death penalty. However, questions seeking to elicit a partisan expert's philosophical views on capital punishment might disclose some bias bearing on his credibility as a witness at the penalty phase. An instruction approved by both parties allowed the jury to consider expert opinion on the death penalty only for this limited purpose.id: 13007
Court did not abuse its discretion in qualifying three officers as experts in an insurance fraud scheme involving staged auto accidents.Defendant was charged with multiple counts of insurance fraud arising from the staging of multiple auto accidents. He argued the court erred when it qualified three police officers as experts without proper foundation as two of the officers did not investigate the instant accidents and the third did not consider the severity of the injuries to the passengers in forming an opinion that an accident was staged. However, the intricacies of a fraudulent scheme are not matters of common experience, and the substantial experience of these three officers in investigating accidents and fraud could only have assisted the jury.id: 13009
Court did not err in disallowing the testimony of psychotherapist who spent less than half an hour with defendant.The trial court did not abuse its discretion in refusing to allow a psychotherapist to testify as to his diagnostic impression of defendant at the sanity phase of the trial. The court based its finding on the fact that the psychotherapist who testified he normally spent two hours with a patient to make an accurate diagnostic impression, spent less than half an hour with defendant.id: 13010
Court did not err in excluding documents relied on by the expert witness.Defense counsel sought to have admitted into evidence various journal articles, and several letters written by defendant, upon which the defense psychiatric expert witness relied in making his evaluation. The doctor did testify at some length about the many documents he reviewed in the course of his evaluation of the case. However, nothing in Evidence Code section 802 requires a trial court to admit into evidence documentary or other evidence of matters relied on by an expert witness in forming his or her opinion.id: 13011
Court did not err by excluding expert testimony opining that imprisoned inmate felons sometimes lie.Appellants argued the trial court erred by excluding their proffered expert testimony from two witnesses, 1) a sociology professor and 2) an expert liar, to the effect that imprisoned inmates sometimes lie, will claim credit for crimes they did not commit, and will give false testimony incriminating others in return for promised benefits from the state. However, there was no abuse of discretion in excluding the proffered evidence. The trial judge properly observed the proposed testimony by the two witnesses in issue would not assist the trier of fact because it was irrelevant and of dubious scientific or testimonial value in considering the question before the jury.id: 13012
Court did not err in permitting prosecution expert witness to testify regarding the doubtful value of certain psychiatric testimony.Defense psychiatrists testified at the penalty phase as to defendant's psychological development and ability to function well in prison. A prosecution witness, a physician specializing in psychiatry then testified regrading the doubtful value of certain psychiatric testimony. Admission of this testimony was neither improper nor prejudicial since the doctor did not suggest the courts bar psychiatrists from the courtroom, his criticism went more to the weight of the earlier opinions rather than their admissibility. Moreover, the jury was instructed they were not bound to accept an expert opinion (such as the prosecution witness') and were entitled to disregard it if unreasonable.id: 13013
Criminalist's use of a probability extrapolation in estimating the weight of the seized cocaine was not improper.Defendant argued the evidence was insufficient to support his conviction as an aider and abettor to the transportation of cocaine and to support the special allegation of the cocaine's weight. He claimed that the expert's opinion that 100 pounds of cocaine was actually contained within the white powder seized by the police was faulty because the expert arrived at the conclusion through a probability calculation based on samples taken from the whole amount. He objected asserting the prosecution failed to comply with <i>Kelly</i> requirements for admitting the evidence. However, the criminalist's use of the probability extrapolation was not a new scientific theory; it was merely a step used in the chemical analysis of contraband. The fact the actual weight was only a representative sampling of the total was relevant to the weight of the expert's testimony, not its admissibilityid: 13017
Evidence established that the expert's opinion was not based solely on potentially incomplete information given her by defendant's wife.Defense at the penalty phase presented evidence that due to psychopathology and polysubstance abuse defendant did not have the capacity to appreciate the criminality of his conduct or to conform his conduct to the law. The People called as an expert on rebuttal, a psychiatrist with a specialty in polysubstance abuse. Her conclusion was based on several factors including an interview with defendant's wife. At one point she stated Perhaps the drug history I got from Allison was incomplete. The court did not abuse its discretion in refusing to bar her testimony. It was apparent from the testimony that the witness' opinion was not based in any significant part on the information in question.id: 13019
Evidence of the child sexual abuse accommodation syndrome was properly admitted after the defense raised the question of victim's credibility.The Kelly-Frye standard of reliability is applicable to testimony of an expert regarding the child sexual abuse accommodation syndrome. Moreover, the CSAAS testimony in the instant case was rehabilitative and thus pertinent to the question of the victim's credibility. Accordingly, it was unnecessary to await the rebuttal stage of trial to be presented. Due to the cross-examination of the victim during the prosecution's case-in-chief, the credibility issue was already fully present in the case and the rehabilitative evidence on the issue was properly admitted.id: 13020
Expert cannot conclude defendant acted impulsively where the expert is otherwise prohibited by section 29 from giving an opinion as to the defendant's state of mind at the time of the crime.Defendant argued the trial court misinterpreted the limitations on opinion testimony embodied in Penal Code section 28, subdivision (a) and section 29, and erred in excluding the opinion of the defense expert that based on defendant's inebriation and tendency to overreact to stress, he fired his rifle impulsively. Section 29 forbids an expert conclusion as to whether a defendant had the requisite state of mind at the time of the crime. By testifying that defendant acted impulsively the expert was suggesting defendant acted without malice aforethought. Contrary to defendant's claim an expert may not testify to defendant's state of mind at the time he acted using words other than the legal name of the state of mind in question.id: 13021
Expert testimony as to why a parent would refrain from reporting a molestation of her child assisted the jury and was properly admitted.Defendant was charged with sexually molesting the 9 year old daughter of his girlfriend. The trial court did not abuse its discretion in admitting the expert testimony of a police officer, trained in child molestation investigations, as to why the victim's mother did not report the incident to authorities. Such evidence was of assistance to the trier of fact under Evidence Code section 801, subdivision (a) by giving the jurors information they needed to evaluate the mother's credibility. Moreover, the evidence was clearly relevant because it tended to rehabilitate the testimony of the mother as a corroborating witness.id: 13022
Expert testimony on child molest victims' reactions was admissible to rebut defense counsel's attack on the victim's credibility.The People's expert witness testified on the reactions of child molestation victims. Defendant argued the expert testimony was improper because the defense did not put in issue any of the paradoxical behaviors of child molest victims, such as recantation. However, the prosecutor explicitly identified the misconceptions about the victim's behavior, i.e., delayed disclosure and inconsistent statements, which the testimony was intended to rebut. There was no error in permitting the expert to testify.id: 13023
Expert testimony that there is no profile on a typical child molester assisted the jury and was relevant to the case and therefore admissible.The trial court did not abuse its discretion in admitting the expert testimony of a police officer trained in child molestation investigation, on the fact that there is no profile of a typical child molester and that such persons are instead found in all walks of life. Such testimony would assist the trier of fact under Evidence Code section 801, subdivision (a) by giving the jurors information they needed to objectively evaluate the People's evidence. The evidence was relevant even though it was admitted during the People's case-in-chief because the jury already knew much about the defendant at that point, and what they knew did not fit the stereotype of a child molester.id: 13024
Expert testimony which assisted the jury in assessing the victim's credibility was admissible under section 801 subdivision (a).A school psychologist testifying for the prosecution stated that the victim had a learning disability which affected his ability to sequence events and put them in chronological order. The testimony concerning the extent of the victim's disabilities as established by the standardized tests was at the very least helpful to the trier of fact in assessing the victim's credibility and was admissible under Evidence Code section 801, subdivision (a).id: 13025
Court properly allowed officer to render an expert opinion that defendant possessed rock cocaine for purposes of sale based on the quantity of the drugs possessed.The trial court did not err in allowing a police officer with extensive training and experience in sales of narcotics, to render an expert opinion that defendant possessed rock cocaine for purposes of sale, based on the quantity of the drugs possessed.id: 12916
Testimony on child sexual abuse accommodation syndrome was admissible on the issue of delay in reporting the incidents.The trial court, after hearing victim's testimony and arguments concerning the propriety of testimony on child sexual abuse accommodation syndrome, limited the psychologist's testimony to be used to rehabilitate the victim's credibility insofar as it is related to his delay in reporting the incidents. The court instructed that the expert may present that evidence only by rendering his opinion of victims as a class and not to this victim in particular. The expert's testimony did not exceed these boundaries.id: 9999
Psychologist's testimony regarding child molest victim's delay in reporting the incident was properly admitted.During defendant's child molest case, the prosecutor called an expert to explain the behavior of the victims in failing to report the incidents. The court instructed the jurors that the expert testimony could not be considered as proof that a molestation in fact occurred. The doctor made clear that she interviewed none of the victim's in the case. Neither the testimony nor the instructions led the jury to believing that the children had in fact been molested.id: 9988
Expert testimony on Child Sexual Abuse Accommodation Syndrome was properly admitted for the limited purpose of explaining why the child molest victim did not immediately report the incident.Defendant was convicted of two count of child molestation. He argued the admission of expert testimony on Child Sexual Abuse Accommodation Syndrome (CSAAS) bolstered the victim's version of the events and violated his constitutional right to confront witnesses and to due process. However, the CSAAS testimony was properly admitted for the limited purpose of explaining why the victim did not immediately inform anyone of the molestation and the court specifically instructed the jury as to its limited use. Moreover, defendant's right to meaningfully cross-examine the victim was not impaired by the introduction of the testimony as he vigorously cross-examined the victim, attacking her creditability. Finally, the introduction of CSAAS testimony to rehabilitate the victim's testimony after rigorous cross-examination did not violate due process.id: 9957
Court did not err in allowing expert testimony concerning behavior common to sexual abuse victims.Defendant argued the court erred in permitting the psychologist to testify over objection concerning behavior common to sexual abuse victims. However, the testimony made clear that the doctor was not offering an opinion on the victim's credibility. The testimony was clearly intended to help explain the victim's delay in reporting the abuse and her last-minute recantation of the charges. The doctor did not suggest the victim's claims were credible simply because she exhibited some behaviors common to abuse victims.id: 9933
About Pat Ford
Pat Ford is a criminal defense lawyer in San Diego who works on appeals in some of the most difficult cases around the state. He has a great record for success and integrity. Pat has also published a criminal case law digest since 1984 that's used by judges and lawyers around the state. He also speaks and writes articles for criminal lawyers as well as consumers interested in the law. The consumer-related articles are intended to be informative but do not constitute legal advice.
Case of the Day
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Exclusion of 18-25 year-olds from the youthful offender provisions of section 3051 did not violate equal protection. Penal Code section 3051 establishes a parole eligibility hearing for juveniles convicted of special circumstance murder and sentenced to life without the possibility of parole. Excluding persons 18-25 from the youthful offender parole hearing provision did not violate equal protection principles.id: 27245