Also known as: Daubert · Daubert standard · Daubert test · Daubert hearing · Daubert rule
Written by attorneys · grounded in primary & secondary sources — see below
A judicial standard requiring federal trial courts to act as gatekeepers ensuring that expert testimony is both relevant and reliable before admission under Federal Rule of Evidence 702. Reliability is assessed through a flexible, case-specific inquiry that may consider factors such as testing, peer review, error rate, controlling standards, and general acceptance.
Daphne Doyle sued Davenport Pharmaceuticals after her son suffered birth defects allegedly caused by a prenatal drug. Davenport offered an aerospace engineer who used a proprietary fluid-dynamics simulation to show that a microburst, not the drug, caused the injury. The district court conducted a Daubert hearing and admitted the testimony after finding the underlying equations tested and the assumptions subject to cross-examination.
Diego Duarte, an investor, sued Dover Bank for securities fraud after a corrective disclosure caused a stock drop. Dover's expert used an event study with a custom small-cap index and selective day exclusions to calculate damages. The district court excluded the testimony because the integrated methodology lacked peer review and created an analytical gap between the data and the damages figure.
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Danielle Dixon sued Drake Logistics alleging patent infringement by its facial-recognition software. Drake offered a computer scientist who relied on an unreviewed internal benchmarking script and laptop tests to claim noninfringement. The district court excluded the testimony after determining that the technical methodology failed reliability standards applicable to specialized knowledge.
Destiny Davis sought to represent a class of employees alleging gender discrimination at Duarte Shipping. Her statistician used a regression model showing pay disparities. The court applied a flexible reliability review to the technical analysis and admitted the testimony because the methods rested on accepted statistical principles and were reliably applied to the employment data.
Derek Douglas was prosecuted for drug trafficking. The government offered an agent's testimony interpreting coded language in recorded calls. The district court performed a case-specific reliability assessment of the specialized interpretive method and admitted the testimony after confirming the technique was grounded in training and experience.
Diane Dawson faced charges after a lab report identified a substance as cocaine. The prosecution sought to introduce the report through an analyst who did not perform the test. The court conducted a flexible inquiry into the technical reliability of the forensic method and excluded the testimony because the application lacked sufficient validation.
The inquiry applies to all expert testimony based on scientific, technical, or other specialized knowledge. Courts must conduct a flexible, case-specific assessment rather than limiting screening to traditional laboratory science.
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Appellate courts review the district court's decision for abuse of discretion. The trial judge's gatekeeping determination receives substantial deference even when the appellate court might have reached a different conclusion.
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Yes. A court may conclude that the gap is too great and exclude the testimony when the expert's conclusions are not supported by sufficient facts or reliable methodology.
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The court applies a flexible inquiry that considers traditional factors along with other indicia of reliability appropriate to the field. Absence of peer review is relevant but not automatically disqualifying if other grounds support reliability.
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Daubert v. Merrell Dow Pharmaceuticals, Inc. <!-- acedexams opinion md v1 -- Case information - Citation: 509 U.S. 579, 592 (1993) Majority opinion Opinion of Judge Kozinski Michael H. Gottesman, Georgetown Univ. Law…