In 1993, in Daubert v. Merrell Dow Pharmaceuticals, Inc., the Supreme Court finally clarified that Rule 702, not Frye, controlled the admission of expert testimony in the federal courts.19 Daubert was a civil case brought by two minor children and their parents, alleging that the children’s serious birth defects had been caused by their mothers’ prenatal ingestion of Bendectin, a prescription drug marketed by the defendant pharmaceutical company. In support of a motion for summary judgment, the drug company submitted an affidavit from a qualified expert, who stated that he had reviewed all the literature on Bendectin and human birth defects and had found no study showing Bendectin to be a human teratogen (i.e., an agent that can cause malformations of an embryo or fetus). The plaintiffs countered with experts of their own, each of whom concluded that Bendectin could cause birth defects. Their conclusions were based on animal studies that found a link between Bendectin and malformations; pharmacological studies of the chemical structure of Bendectin that purported to show similarities between the structure of the drug and that of other substances known to cause birth defects; and the “reanalysis” of previously published epidemiological (human statistical) studies. The district court held that the expert testimony proffered by the plaintiffs was inadmissible, because their scientific evidence was not sufficiently established to have general acceptance in the field to which it belonged.20 The court of appeals, citing Frye, affirmed the judgment of the district court, declaring that expert opinion based on a methodology that diverges significantly from the procedures accepted by recognized authorities in the field cannot be shown to be generally accepted as a reliable technique.21 The Supreme Court reversed, holding that the trial court had applied the wrong standard in assessing the expert testimony proffered by the plaintiffs. The case was then remanded for further proceedings.
In construing and applying Rule 702, the Daubert Court ruled that a “trial judge must ensure that any and all scientific testimony or evidence admitted is not only relevant, but reliable.”22 The Court rejected the Frye test, noting that the drafting history of Rule 702 made no mention of Frye,
issues, and superfluity.”); J.W. Strong. Questions affecting the admissibility of scientific evidence. U. ILL. L.F. 1, 14 (1970) (“The Frye standard, however, tends to obscure these proper considerations by asserting an undefinable general acceptance as the principal if not sole determinative factor.”).