Also known as: Daubert · Daubert standard · Daubert test · Daubert ruling · Daubert v. Merrell Dow
Written by attorneys · grounded in primary & secondary sources — see below
A Supreme Court decision establishing that federal district courts must serve as gatekeepers under Federal Rule of Evidence 702 to admit only expert testimony that is both relevant and reliable. Reliability is evaluated through a flexible case-specific inquiry that may consider whether the expert's theory or method has been tested, subjected to peer review and publication, possesses a known or potential error rate, is governed by controlling standards, and enjoys general acceptance in the relevant field. The decision extends the reliability requirement to all forms of expert testimony based on scientific, technical, or other specialized knowledge.
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Dorothy Daniels sued Duffy Construction after a crane collapse injured her. Duffy offered an aerospace engineer who used a proprietary fluid-dynamics model tested only in university wind tunnels. The district court conducted a Daubert hearing and admitted the testimony after finding the underlying principles tested and the assumptions open to cross-examination.
Delilah Duran sued Dover Bank alleging securities fraud. The bank proffered an economist whose event study used a custom index and excluded trading days without publishing the combined method. The district court excluded the testimony because the conclusions rested on an impermissible gap between the data and the opinion offered.
Derek Douglas sued Decker Electronics for patent infringement. Decker offered a computer scientist whose benchmarking script had never been peer-reviewed outside the company and whose error-rate estimates came from informal laptop tests. The district court excluded the testimony after finding the methodology unreliable for technical expert evidence.
Destiny Davis sought to represent a class of employees against Delta Dynamics. Her statistician relied on internal payroll data and a regression model never validated against industry benchmarks. The court applied a flexible reliability inquiry and excluded the testimony because the method lacked sufficient testing and controlling standards.
Darrell Duncan faced criminal charges and sought to introduce polygraph results through an examiner using an unvalidated scoring protocol. The court conducted a gatekeeping review and excluded the evidence because the technique had not been shown reliable under the flexible Daubert factors for specialized knowledge.
Denise Donovan sued after a vehicle rollover and objected to an accident-reconstruction expert who relied on a proprietary crash database never subjected to external validation. The court performed a case-specific reliability analysis and admitted the testimony after determining the methodology was sufficiently grounded for technical expert evidence.
The decision requires federal courts to act as gatekeepers under Rule 702 to ensure expert testimony is both relevant and reliable before it reaches the jury. Reliability is assessed through a flexible case-specific inquiry that may consider testing, peer review, error rate, controlling standards, and general acceptance.
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No. The analysis extends to all expert testimony based on technical or other specialized knowledge, including engineering and computer-science methods. Courts retain discretion to consider the traditional factors or other appropriate indicia of reliability suited to the field.
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.…
…J., filed an opinion concurring in part and dissenting in part. Majority opinion Opinion of Justice Breyer In Daubert v. Merrell Dow Pharmaceuticals, Inc. , 509 U. S. 579 (1993), this Court focused upon the admissibility of scientific expert
…what standard an appellate court should apply in reviewing a trial court’s
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Appellate courts review a district court's decision to admit or exclude expert testimony for abuse of discretion. A court may exclude testimony when there is too great an analytical gap between the data and the opinion offered.
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No. The factors are illustrative and not a rigid checklist. Courts conduct a flexible inquiry and may consider any indicia that logically bear on whether the methodology is reliable and properly applied to the facts.
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