Daubert Gatekeeping
Definition
The judicial function under Daubert v. Merrell Dow Pharmaceuticals (1993) and Federal Rules of Evidence Rule 702, requiring the trial judge to assess the scientific reliability and relevance of expert methodology before the expert testifies. The criteria include peer review, known error rate, testability, and general acceptance.
- Origin case
- Daubert v. Merrell Dow Pharmaceuticals, 1993
- Governing rule
- Federal Rule of Evidence 702
- Who applies it
- The trial judge, before the expert testifies
- Key factors
- Testability, peer review, known error rate, general acceptance
- Jurisdiction
- US federal courts and most US states
Common questions
What happens if an expert's method fails Daubert scrutiny?+
The judge can exclude the testimony entirely before the jury ever hears it, or limit what the expert is permitted to say. This makes the gatekeeping hearing, often called a Daubert hearing, a pretrial event separate from the trial itself, and losing one can end a case's reliance on that expert.
How does Daubert differ from the older Frye standard?+
Frye asked only whether a method had gained general acceptance in the relevant scientific community. Daubert replaced that single question with a multi-factor reliability test the judge applies directly, giving the court more discretion to evaluate novel or minority methods on their merits rather than deferring to consensus.
Does every US court use the Daubert standard?+
No. Most federal courts and a majority of states apply Daubert or a close variant, but some states still use Frye or a hybrid standard. An expert should confirm which standard governs before a case, since the admissibility bar and the hearing procedure differ.
Related terms
- Cross-Examination
- Questioning of a witness by the opposing party. For an expert, cross-examination probes qualifications, methodology, the basis of opinions, limitations, inconsistencies with...
- Abuse of Discretion
- The standard of appellate review established by Joiner for Daubert rulings. An appellate court will reverse a trial judge's gatekeeping decision only...
- Concession
- An acknowledgment by the expert witness that a particular proposition put by counsel is correct. A partial concession accepts part of a...
- Daubert Trilogy
- The three US Supreme Court decisions that together define the federal standard for expert testimony admissibility: Daubert v. Merrell Dow Pharmaceuticals (1993),...
- Error Rate
- One of the Daubert factors: the known or potential rate at which a method produces false positives or false negatives, and whether...
- Examination-in-Chief
- The questioning of a witness by the party who called them. For an expert, this is typically limited because the substance is...
- Expert's Duty to the Court
- The overriding obligation, recognised in common law and many civil law systems, that the expert's evidence must be honest, independent, and complete,...
- Federal Rule of Evidence 702
- The US federal rule governing expert testimony. As amended through 2023, it requires that expert opinion be based on sufficient facts or...
- Frye Standard
- The US legal test for admissibility of scientific evidence, originating from Frye v. United States (1923), which required that a technique be...
- Likelihood Ratio
- A statistical expression of the strength of evidence: how much more probable the observed findings are if the prosecution's hypothesis is true...
- Overreaching
- The error of stating a conclusion that the underlying data does not support. Overreaching is the single most common reason experts are...
- Pre-Trial Conference
- A meeting between the forensic expert and instructing counsel held before the hearing to agree on scope, clarify limitations, identify likely challenges,...
Explained in these topics
- Preparing to Testify as a Forensic ExpertUnder the US Daubert standard, the trial judge has a duty to assess the scientific validity of proposed expert methodology before allowing it before the jury....
- Surviving Cross-Examination
- The Daubert Standard and Its ProgenyThe obligation, placed on trial judges by Daubert v. Merrell Dow Pharmaceuticals (1993) and Federal Rule of Evidence 702, to assess the reliability and relevan...