Subject Matter for Expert Testimony
Before an expert ever speaks to the jury, the trial judge stands at the door as a gatekeeper, and the single question the Nevada FLE tests is whether the subject of the propos
7. Subject Matter for Expert Testimony
Trial judges serve as gatekeepers for expert testimony, determining whether the subject of an expert’s proposed testimony is sufficiently reliable to present to a jury.
- This rule, like the others in this section, attempts to shield the jury from misleading testimony.
- Before allowing an expert to testify, the trial judge must determine that “the testimony is the product of reliable principles and methods.” Fed. R. Evid. 702(c).
- When making that determination, judges consider the factors set out in Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993). These include:
- Whether the theory or technique has been tested;
- Whether it has been subject to peer review and publication;
- The technique’s error rate;
- The existence of standards controlling the technique’s application; and
- Any other factor useful in determining the scientific validity of the principles underlying the expert’s testimony.
- None of the Daubert factors are dispositive. In particular, a judge may find subject matter sufficiently reliable even if the expert’s technique or theory is not generally accepted in the scientific community.
- The party offering expert testimony bears the burden of proving (by a preponderance of the evidence) the reliability of that evidence.
- If the judge determines that the subject of proposed expert testimony is sufficiently reliable, then the expert may testify “in the form of an opinion or otherwise.” Fed. R. Evid. 702.
- The Nevada FLE does not test knowledge of other requirements related to the subject matter of expert testimony. The exam focuses solely on the requirement of reliability stated in Rule 702 and the Daubert opinion.
- Principle Three: Second-hand Statements (Hearsay) Are One Type of Evidence That
- May Mislead Jurors. The Rules Exclude Many, But Not All, of Those Statements.
- Note About the Sixth Amendment: The Supreme Court has developed a complex body of
- case law analyzing Sixth Amendment Confrontation Clause constraints on the admission
- of statements under some hearsay exceptions. The Nevada FLE does not test that case
- law, which continues to evolve. FLE Evidence questions are constructed to avoid raising
- any possible Confrontation Clause concerns.
The trial judge is a gatekeeper, and the only tested question is whether the subject of the proposed testimony is sufficiently reliable, meaning the product of reliable principles and methods.
Before an expert ever speaks to the jury, the trial judge stands at the door as a gatekeeper, and the single question the Nevada FLE tests is whether the subject of the proposed testimony is sufficiently reliable to be heard. Reliability here means one thing: the testimony must be the product of reliable principles and methods. To decide that, the judge weighs the Supreme Court's reliability factors, including whether the theory or technique has been tested, whether it has been subjected to peer review and publication, its known or potential error rate, whether standards control its application, and any other factor that bears on scientific validity.
Two points carry most of the tested weight. First, none of these factors is dispositive, and in particular general acceptance in the relevant scientific community is not required, so a judge may admit reliable testimony even when the technique is not generally accepted. Second, the burden of proving reliability rests on the party offering the expert, the proponent, who must establish it by a preponderance of the evidence, not on the opponent and not by any higher standard.
If the judge is satisfied that the subject matter is sufficiently reliable, the expert may testify in the form of an opinion or otherwise.
The exam tests reliability only, so the expert's qualifications, the helpfulness or fit of the testimony, whether it rests on sufficient facts or data, reliable application to the facts, and disclosure are all outside what is tested here.
gate keeps junk out: judge as GATEkeeper asks is it reliable, weighs the factors where none controls and general acceptance is not required, and the proponent carries it by a preponderance.
A party offers a forensic analyst to testify about a novel pattern-matching technique. The opposing party objects, arguing the technique is too new and is not yet generally accepted in the relevant scientific community.
An option treats general acceptance in the scientific community as required, or makes it the threshold test for admissibility.
No single factor is dispositive and general acceptance is not required; a judge may admit reliable testimony even without it.An option puts the burden on the opponent to disprove reliability, or demands clear and convincing evidence.
The proponent (the party offering the expert) bears the burden, by a preponderance of the evidence.An option makes one factor (peer review, low error rate, or testing) a mandatory prerequisite, or says satisfying one factor automatically settles reliability.
None of the reliability factors is dispositive in either direction; the judge weighs all of them.An option resolves admissibility on the expert's qualifications, on helpfulness/fit, on sufficient facts or data, or on disclosure.
The exam tests reliability of the subject matter only; those other requirements are excluded from scope.An option reaches the correct yes/no result but grounds it in the wrong reason, such as a party's concession rather than the subject's reliability.
Admission turns on the subject being the product of reliable principles and methods, not on a concession or a collateral fact.any objection to proposed expert testimony that turns on whether the subject is sound enough to reach the jury (novel technique, disputed methodology, a fight over peer review, error rate, or general acceptance).
Run the check in this order: identify the judge's gatekeeping role; ask the only tested question, is the testimony the product of reliable principles and methods; weigh the reliability factors while remembering none is dispositive and general acceptance is not required; confirm the burden sits on the proponent by a preponderance; and discard any answer that decides the issue on qualifications, helpfulness, sufficiency of facts, or disclosure, because the exam tests reliability of the subject matter only.
A party offers an engineer to testify about a relatively new analytical technique. The opposing party objects, conceding the technique has been tested and peer reviewed but arguing that it is not yet generally accepted in the relevant scientific community. The trial judge concludes that the technique is the product of reliable principles and methods.
May the trial judge admit the testimony even though the technique is not generally accepted?
At a hearing on the admissibility of proposed expert testimony, the party offering the expert and the opposing party dispute whether the underlying methodology is sufficiently reliable. Neither side has clearly established who must carry the point.
Who bears the burden of proving the reliability of the proposed expert testimony, and by what standard?
A party offers a chemist to give opinion testimony based on a method that has not been published or peer reviewed. The opposing party argues that, because the method has never been subjected to peer review and publication, the trial judge must exclude the testimony as unreliable. The judge finds that the method has been tested, has a low error rate, and is governed by controlling standards.
Must the trial judge exclude the testimony solely because the method has not been subjected to peer review and publication?
A party offers a witness as an expert. The opposing party challenges only the reliability of the subject matter of the proposed testimony and does not dispute the witness's training or experience. At the admissibility hearing, the judge becomes focused on whether the witness is adequately qualified by credentials.
On what question should the trial judge's reliability ruling turn?
After a contested hearing, the trial judge determines that the subject of an expert's proposed testimony is sufficiently reliable because it is the product of reliable principles and methods. The proponent then asks how the expert will be permitted to testify.
Once the judge finds the subject matter sufficiently reliable, in what form may the expert testify?