ONCALL
...Evidence
......Opinion & Scientific Evidence
 128 Cards On This Topic:
  • TruNarc drug test evidence improperly admitted as it is based on a new scientific technique and the DA failed to show its reliability or general acceptance in the relevant scientific community within the meaning of the Kelly rule.
  • Reversible error to repeatedly allow lead detective's opinion that he based on other Ws' testimony; his testimony that D fired the weapon was "too helpful" and supplanted jury's role.
  • Sanchez precludes an expert in a Family Law case from relying on and relaying case-specific hearsay unless evidence that would independently prove the fact is admitted.
  • Error to exclude causation E's testimony as there is no requirement that E rely on a specific study or other scientific publication expressing precisely the same conclusion at which s/he has arrived; court overstepped gatekeeper role.
  • Trial ct. properly admitted CSAAS-equivalent expert testimony focused on dispelling myths or misconceptions about how CSA victims might be expected to act.
  • "[T]o create an inference of intentional discrimination, statistics must demonstrate a significant disparity and must eliminate nondiscriminatory reasons for the apparent disparity."
  • Because P's medical expert was qualified and his opinion was based on facts and a differential diagnosis, trial court erred in excluding his evidence that P's illnesses were caused by excess mold in her leased residence.
  • Trial court not required to follow expert opinion.
  • Expert medical opinion evidence that is based upon a guess, surmise or conjecture, rather than relevant, probative facts, cannot constitute substantial evidence.
  • Experts should use a standard violence risk assessment when opining on likelihood of future violence, rather than unstructured clinical judgment.
  • DA has no right to privately retain an expert under the SVPA; expert witness provisions of the Civil Discovery Act do not apply.
  • Sufficient details re DNA evidence in O's affidavit established probable cause for the search of D's trash can.
  • In evaluating expert's application of relevant criteria, court did not impermissibly weigh the evidence but considered whether his methodology was reliable.
  • Expert testimony on interpretation of foreign law not relevant to question of whether Father abducted child in violation of foreign decree.
  • No error in admitting expert's testimony on CSAAS statistics to show how often abused Cs know their abuser, and how often they delayed reporting, when used for victim credibility, not as vouching.
  • D's corporate representative, designated as the "person most knowledgeable," still testifies as a lay witness, not an expert.
  • Ds failed to show reversible prejudice from admission of E's testimony that fibrous talc can cause mesothelioma; testimony not subject to exclusion under Sargon.
  • Harmless error to admit evidence murder V's blood tested negative for alcohol where foundational elements for toxicology test results not met.
  • Trial ct. failed to apply reasonable person standard re probable cause, improperly rejecting E's opinion based on its personal belief ill, 70-yr.-old D still qualified as an SVP.
  • Limitations Sanchez placed on expert testimony concern case-specific information an expert relates to a jury, not materials upon which the expert relies.
  • Ps had notice at admin. hearing of Ws’ anticipated testimony and reasonable opportunity to respond where DRE, in prehearing conference statement, I.D.'d the Ws it intended to call and described their expected testimony.
  • Evidence insufficient to support commitment extension under PC §1026.5 where it showed medicated D with schizoaffective disorder could control his dangerous behavior.
  • Any Sanchez error based on experts' reliance on co-D's jailhouse statements regarding the meaning of D's tattoos was harmless.
  • Challenge to admitting expert testimony is a challenge to the reliability and foundation of the evidence, and whether the subject is admissible as expert testimony; must be raised at trial.
  • Expert testimony about the reputational benefits of crime does not alone support an inference that lone gang member committed a crime for gang-related, rather than personal, reasons.
  • Gang evidence admissible to bolster witness I.D. and where D himself identified gang affiliation as a motive.
  • Expert-witness provisions of the Civil Discovery Act do not apply in SVPA proceedings and the DA may not call privately-retained expert witness to testify at trial.
  • Eyewitness testimony about the speed of D’s car was proper.
  • Although expert could not opine on the amount of marijuana D had smoked, testimony was sufficient to establish D was impaired.
  • Expert's opinion testimony about the results of a GSS test showing D was highly suggestible and susceptible to giving a false confession was improperly excluded.
  • The party without the burden of proof must be allowed to suggest alternative causes, or the uncertainty of causation, to less than a reasonable medical probability.
  • Expert testimony properly admitted to show a mark on body could have been made by handcuffs.
  • Expert testimony in tool mark analysis need not satisfy the Kelly rule’s requirements of expert reliability.
  • Witness qualified as an expert on tool mark identification based on experience, rather than training.
  • The modern tendency is to permit lay opinions where they are "helpful" in understanding testimony.
  • The STRmix method of DNA analysis has gained general acceptance within the relevant scientific community.
  • Experts who testify as to a technique's general acceptance must be disinterested and impartial.
  • The fact the computer source code had not been tested by the ••broader•• scientific community does not mean it has not been approved by the relevant scientific community.
  • Introduction of hearsay at a custody hearing not reversible error absent showing of prejudice.
  • An eyewitness expert’s testimony about the fallibility of eyewitness testimony is proper lingering doubt testimony in a penalty phase.
  • Expert opinion not required to establish inference of causation for a fall from unsafe stairs.
  • Mother's failure to introduce a bonding study in a termination of parental rights hearing permitted an inference neither child had a significant, positive emotional attachment to her.
  • Expert testimony explaining the absence of fingerprint evidence proper.
  • Witness statements that merely explain the context of a conversation are admissible.
  • After expert educates jurors, the factual issues in the case become ones the jurors can answer as easily as the expert.
  • Hearsay testimony D was a member of a gang harmless where jury would have learned that from other evidence.
  • Sanchez error harmless where other evidence established the requisite fact.
  • The opinion of an expert is no better than the reasons upon which it is based.
  • A medical diagnosis based on probability is admissible; the lack of scientific certainty does not deprive the medical opinion of its evidentiary value.
  • An absent witness’s opinion may not be smuggled into evidence through an expert by dressing it up as background information.
  • The rule an expert may not testify differently than at a deposition does not apply to summary judgments where there has been no determination the testimony would be inadmissible at trial.
  • W&IC §6602(a) does not create an exception allowing hearsay regarding nonpredicate offenses to be introduced in a SVP probable cause hearing via evaluation reports.
  • Expert's testimony should not be rejected simply because it is based on inadmissible evidence; court must consider the reliability of the data used.
  • Testimony of expert who conducted additional work after being excused to buttress evidence which had been excluded properly struck because other party had no opportunity to depose.
  • Expert's testimony should not be rejected simply because it is based on inadmissible evidence; court must consider the reliability of the data used.
  • Damages under a Rent Ordinance may be calculated using “rent differential” method.
  • Requirements to show that evidence was false and that it was essential to the conviction.
  • CSAAS properly admitted to disabuse jurors of commonly held myths or misconceptions about child sexual abuse.
  • CSAAS testimony is not “scientific evidence” subject to the Kelly rule.
  • E's testimony it was "rare" for children to falsely report sexual abuse was akin to vouching for the veracity of the victims.
  • A gang enhancement must be proven by independently admissible evidence, not solely by the testimony of an expert who has no personal knowledge of facts otherwise necessary to satisfy the prosecution’s burden.
  • The habits and culture of young men who socialize widely, including with gang members, is not a matter “beyond common experience [such] that the opinion of an expert would assist the trier of fact.”
  • That the trial court may have ••heard•• inadmissible case-specific hearsay, does not overcome the presumption it applied Sanchez and properly ignored such material.
  • ShotSpotter evidence improperly admitted without first conducting an evidentiary hearing to assess its scientific reliability pursuant to Kelly/Frye.
  • Failure to object to Es' inadmissible testimony concerning D's guilt constituted ineffective assistance of counsel.
  • CSAAS evidence is not admissible to prove the complaining witness has in fact been sexually abused.
  • Officers' reliance on CPS computer file hash value to identify child pornography did not violate Sanchez hearsay prohibition.
  • Child Protection System (CPS) is not a technique or process; it is a program that deploys a technique or executes a process and is not subject to Kelly-Frye.
  • Computer programs which repeatedly perform simple tasks that previously would have taken extensive human labor to complete in the same quantity are not inadmissible under Sargon.
  • CALJIC 315's eyewitness certainty instruction is potentially misleading; may not be used until Judicial Council reviews it.
  • Expert's testimony relating as true statements made to him by D was barred by Sanchez.
  • An expert’s testimony in prior cases involving similar issues is a legitimate subject of cross-examination when it is relevant to the bias of the witness.
  • An expert's declaration submitted in opposition to a summary adjudication is not subject to as strict a scrutiny as one offered at trial.
  • ShotSpotter evidence improperly admitted without first conducting an evidentiary hearing to assess its scientific reliability pursuant to Kelly/Frye.
  • Presumption DMV blood tests were properly conducted may not be overcome by showing a violation of governing regulations having only a tenuous connection to the accuracy of the results.
  • Expert opinion has no value if its basis is unsound; may not base conclusion solely on experience.
  • When the continuing admissibility of tool marks ballistic comparison is at issue, the burden shifts to the opposing party to produce new evidence showing it is no longer generally accepted as reliable.
  • When the continuing admissibility of scientific evidence is at issue, the burden shifts to the opposing party to produce new evidence showing it is no longer generally accepted as reliable.
  • The expert's opinions are limited to what is actually supported by the material the expert relied on.
  • An expert's testimony that his opinion had been reviewed and approved by a supervisor violates Sanchez.
  • A declaration as to the existence of a backup storage system for emails does not require the witness qualify as an expert.
  • Kelley inquiry not required for admissibility of DNA product rule in a cold hit case.
  • There are three accepted methods for expressing the statistical significance of a DNA match following a database search; as all are reliable, the issue is relevance.
  • An autopsy report prepared by another which was not admitted into evidence under a hearsay exception cannot furnish the basis for an expert's opinion.
  • An officer who has extensively reviewed a video may offer a narration, pointing out particulars that a casual observer might not see.
  • Dog trailing evidence is not subject to the People v. Kelly test.
  • Requirements for admissibility of dog trailing evidence summarized; People v. Kelly hearing not required; evidence of cue avoidance not required.
  • Jurors are permitted to conduct experiments so long as they do so within "scope and purview of the evidence."
  • Opinions on guilt or innocence are inadmissible because they are of no assistance to the trier of fact, who is as competent as the witness to weigh the evidence and draw a conclusion on the issue of guilt.
  • Although expert lacked qualifications of comparable experts, he had relevant on-the-job training and experience which permitted him to testify as an expert.
  • The great majority of courts approve of CSAAS expert rebuttal testimony.
  • CSAAS evidence consists of the expert’s clinical experience and is not subject to the Kelly/Frye rule.
  • CSAAS evidence is not subject to Kelly/Frye because courts have long recognized the well-established relevance, necessity, reliability, and importance of this evidence.
  • Bare conclusion of D’s expert, unsupported by reasons or explanations, is insufficient to show D acted within the standard of care.
  • Summary judgment properly granted where medical expert’s opinion was rendered without a reasoned explanation as to why the underlying facts led to the conclusion that hospital's nurses and doctors were negligent.
  • Summary judgment correctly granted where medical expert's declaration was predicated on the opinion contained in a second medical expert's declaration.
  • Medical doctor's declaration properly excluded for lack of foundation where it baldly stated his expert opinion was "based on his experience and documented medical literature."
  • Expert's declaration properly excluded where his medical qualifications did not extend to his specific opinions on cause or treatment of decedent's stroke.
  • Expert's testimony that pickup truck's fuel pump relay was a possible cause of vehicle power loss properly precluded where testimony was speculative.
  • Judge stating he did not see evidence consistent with what he would expect after a forcible rape did not establish a "probability of actual bias on the part of the judge"; rape trauma syndrome evidence recognized.
  • E’s testimony that he relied on a database to determine the contents of the pills found on D’s person was not case-specific hearsay.
  • Where defendant did not make a hearsay objection to expert testimony two days before Sanchez was decided, defendant's Sanchez claim on appeal was not forfeited.
  • Under Sanchez, a gang expert may testify to non-case-specific general background information about a gang based upon hearsay.
  • Expert's opinion on defendants' sales costs properly excluded where it lacked foundation; summary judgment properly granted.
  • The rule against the admission of case-specific hearsay via expert opinion stated in People v. Sanchez applied to a sexually violent predator probable cause commitment hearing.
  • Under Sanchez, a gang expert may testify to non-case-specific general background information about a gang based upon hearsay.
  • Finding of probable cause in a sexually violent predator proceeding vacated where court allowed two experts to relate case-specific hearsay about an alleged sexual assault in violation of Sanchez.
  • Judgment reversed in personal injury trial where defendant's undesignated medical expert witness exceeded the scope of permissible impeachment under CCP §2034.210.
  • Based on his training and experience, correctional officer could properly give expert testimony regarding D's smuggling of methamphetamine into prison.
  • Any Sanchez error was harmless where hearsay exception applied and content of text messages was independently proven through forensic cell phone reports.
  • No abuse of discretion in allowing a former police officer to testify as an expert in field sobriety where he had 25 years of experience as an officer, including certification in DUI matters.
  • H&SC §1799.110(c) does not limit all expert medical testimony in a suit against an emergency room doctor; it applies only to medical testimony regarding the standard of care.
  • Medical examiner's expert testimony regarding victim's cause of death did not violate Sanchez because an expert may rely on hearsay when forming an opinion, and may tell the jury in general terms that he did so.
  • Trial ct. properly allowed expert to testify about factors jury should consider when evaluating a child witness' credibility, and properly prohibited expert from specifically commenting on child witness' credibility.
  • Expert statistical probability evidence is inadmissible to prove that a child was abused as witness credibility is an issue solely for the jury.
  • W’s testimony she felt threatened by H was properly admitted as lay opinion.
  • Expert witness was unnecessary to establish real estate broker's conduct constituting breach of duty where circumstances were within the common knowledge of layman.
  • Summary judgment properly granted where plaintiff's expert's declaration neither stated the basis for his opinion nor stated any facts or reasons to support it.
  • Gang expert's case-specific testimony barred by the confrontation clause and state law under Sanchez; error harmless.
  • Plaintiff's experts on damages properly excluded from testifying where their opinions were based on hypothetical conjecture.
  • The hearsay rule of Sanchez applies only prospectively and is not retroactive.
  • Trial ct. had discretion to exclude defendant's eyewitness identification expert where the prosecution's case was substantially corroborated by other evidence placing defendant at the scene of the crime.
  • An officer may testify as to the significance of a defendant’s performance on an HGN field sobriety test without separate expert testimony.
  • Upon plaintiff's motion for summary judgment, trial ct. properly excluded declaration of defendant's expert where it lacked adequate foundation and analysis, and made legal conclusions.
  • Under Sanchez, an expert witness may not relate as true the case-specific content of documents which were neither admitted into evidence nor shown to be covered by a hearsay exception.
  • Under Sanchez, psychiatric expert could testify to case-specific facts in psychiatric patient's records that were ruled admissible under the business records exception of the hearsay rule.
  • Sanchez precluded expert from relating case-specific hearsay facts about V's mental condition and aggressive behavior in hypothetical form.
  • Expert’s testimony that he relied on a database to determine the contents of the pills found on defendant’s person was not case-specific hearsay.


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