Economics in Law Through an Evidentiary Lens: Appraising the Paradox of Daubert as Applied to Social Science Testimony

In this paper I address the question: Is social science a science for the purposes of determining admissibility of expert witness testimony? Under the Supreme Court's interpretation of Rule 702 of the Federal Rules of Evidence in Daubert v. Merrell Dow Pharmaceuticals, Inc., the trial court judge can exclude the testimony of an expert witness if it is not the product of valid scientific methodology. The following four "Daubert factors," articulated by the Supreme Court, aid in determining the validity of scientific methodology: (1) testability of the testimony; (2) publication and peer review of the testimony; (3) error rates underlying the testimony; and (4) general acceptance of the method used to derive the testimony. My question of whether social science is a science is equivalent to asking whether social science conforms to the requirements of Daubert. My answer is that social science is a science under Rule 702, but that the "Daubert factors," rooted in natural science principles, are too limiting to apply to social science. As a result, lower courts have been confused and inconsistent in applying the factors to the testimony of social scientists, and especially economists. Some courts have treated the factors as independent; some have attempted to balance; and some have openly ignored the factors. The result is an incoherent set of evidentiary rulings that have affected the substantive law in such areas as Antitrust, Title VII, Intellectual Property, Contract and Torts, and Remedies (especially hedonic damages). Commentators, such as Professors Faigman and Wilson, have added to the confusion by recommending that lower courts be more aggressive in excluding social science testimony for lacking scientific validity. Such commentators, motivated by a desire to exclude syndrome testimony in criminal cases, ignore the implications of such an aggressive reading of Daubert for other substantive areas of the law. Courts and commentators have failed to recognize the natural law context in which the "Daubert factors" were developed. Lower courts and commentators in their application of the four factors have been too methodologically rigid in scrutinizing social science. Although the Court in Daubert did not specifically address social science testimony, the Court did mandate an appeal to the relevant scientific community for clarity on standards of methodological validity. Lower courts have not pursued this mandate and commentators have ignored it in their policy recommendations. After surveying the case law and dissecting the Daubert opinion and the discussion of many commentators, I conclude that an approach that considers the factual and logical foundations for the testimony allows for both flexibility in application and rigorous scrutiny by the trial court judge. This more flexible approach, adopted from the amici brief of the Historians of Science, would apply equally to the natural and social sciences. I demonstrate how this approach would be applied to testimony in the area of Antitrust, Contracts, Intellectual Property, Title VII, and hedonic damages. Although in many instances the results do not change, my approach has the advantage of being consistent and promoting predictable results. My approach is less draconian in the exclusion of experts than perhaps many commentators would find desirable. However, my more flexible approach is less likely to open the courtroom to "junk science" than the Daubert approach as currently applied. I conclude the paper by directly addressing commentators who recommend using Daubert to exclude social science testimony, particularly testimony pertaining to syndromes. I argue that using evidentiary rules to reach such substantive ends, while arguably efficient, is politically illegitimate in the case of syndrome evidence. Furthermore, such a recommendation is not a valid reading of Daubert, which requires scrutiny of method but appeal to the scientific community to understand valid method. Commentators have dubbed the prevalence of "junk science" in the courtroom "Galileo's Revenge." I propose that attempts to use law to redefine science to reach certain substantive ends should candidly be called "Bellarmine Syndrome."