Sheila Jasanoff and Sean O?Donnell

In 1993, the US Supreme Court issued a landmark decision, Daubert v. Merrell Dow Pharmaceuticals, Inc., that changed the rules for managing the quality and flow of scientific evidence into federal courts. Daubert charged trial judges with the responsibility to act as ?gatekeepers? for scientific evidence and to ensure that such testimony was both reliable and relevant. This project examines the impact of Daubert on science and justice and documents the translation of a legal decision into practices in the legal process.

Specifically, the project addresses the following questions: Did the decision succeed with respect to its primary objective: to keep unreliable and irrelevant expert testimony (popularly known as "junk science") out of courts? What was the effect of requiring trial judges to "think like scientists"? To what extent did Daubert stimulate the production of new scientific knowledge? Has Daubert impeded the introduction of valid scientific knowledge as evidence? Has Daubert promoted justice?

The project will address these questions with a mix of qualitative methods. A searchable database will be created of state and federal decisions across four "hotspot" jurisdictions representing ?liberal? and ?restrictive? interpretations of Daubert. Claims of chemical and drug-induced injuries and their associated forms of evidence and expertise will be tracked and analyzed. Case studies will be prepared of two high-profile post-Daubert lawsuits involving evidentiary conflicts: litigation over phenylpropanolamine (PPA), a drug suspected of causing strokes; and over silicone gel breast implants, alleged to cause immune system disorders. Trial documents and videotaped testimony will be analyzed and personal interviews will be conducted to provide in-depth understanding of the uses of expert evidence after Daubert.

The project will document and preserve the early history of Daubert's implementation by archiving pertinent written texts, videos, and interviews so as to assist future researchers in law and science. Project results will also help improve the education of judges, litigators, and expert witnesses.

Project Report

Between 1993 and 1999, the US Supreme Court decided three landmark cases governing the admissibility of expert testimony in federal courts. The first of these, Daubert v. Merrell Dow Pharmaceuticals, Inc., held that—instead of the older Frye rule of "general acceptance"—the Federal Rules of Evidence, requiring expert evidence to be relevant and reliable, govern whether scientific testimony should be admitted in court. Daubert asked judges to assume primary responsibility for ensuring that evidence meets reliability standards acceptable to scientists. Judges, in short, were asked to "think like scientists" and to act as gatekeepers to exclude unreliable evidence. Daubert provided several examples of criteria that judges might apply in assessing reliability, most notably: (1) whether the expert's technique or theory can be or has been tested; (2) whether the technique or theory has been subject to peer review and publication; (3) the known or potential rate of error of the technique or theory when applied; (4) whether the technique or theory has been generally accepted in the scientific community. This project sought to evaluate Daubert’s impact on legal decisionmaking by qualitatively investigating the caselaw since the trilogy of evidence decisions was decided. One important result was to improve our understanding of the concept of evidence. Trials, as our results show, function as a means of recreating events that require moral evaluation in front of actors (judges or juries) who are authorized by the legal system to render such judgments. Put differently, a trial seeks to replicate past events as exactly as possible before a moral adjudicator, who then decides how to allocate responsibility for claimed harms. Reliable evidence, then, is any testimony which in the judge’s view allows the events that gave rise to the dispute in question to be accurately re-represented in court. In turn, as this project found, the effort to reenact or precisely replicate past events tends to favor the testimony of the eyes above other forms of representation. An analysis of oral arguments and opinions in the evidence trilogy indicates that the Court did not abandon the longstanding judicial preference for testimony that allows judges in effect to "see" past events as they really happened. A second finding is that Daubert’s impact was significantly and unexpectedly affected by parallel independent developments in information and communication technologies. With the rise of the Internet, Daubert implementation became a far-reaching commercial enterprise, enabling varied for-profit services such as the "Daubert Tracker" and Mealey’s Daubert Report, as well as many blogs and sites maintained by individual firms and legal experts. These offer compilations of Daubert cases and materials, including legal briefs and guides to expert witnesses, as well as strategic guidance on how to litigate such cases. Through these developments Daubert may have had more impact on the nature of lawyering than on the quality of scientific evidence. Another unexpected finding is that concern for the reliability of expert evidence arose in other national legal systems—both common and civil law—in the same period, but very different solutions were recommended and adopted. In the United Kingdom, cost and delay were primary concerns, impeding access to justice; one response was to reduce the number of experts called to testify. In Australia, biases introduced through adversarial cross-examination by attorneys were seen as important barriers to reliable fact-finding, and a novel process was designed whereby experts for the parties may question each other directly in the judge’s presence. In the Netherlands, a civil law jurisdiction, concern focused on shoddy expertise leading to false convictions in criminal cases; one response was to create a national register of experts for prosecutorial use. Despite many differences in the creation of national registers, and in the degree of the state’s discretion to call unregistered experts, European systems appear to have devoted greater attention to the reliability of individual expert witnesses than to the reliability of specific bodies of knowledge. In the United States, by contrast, charges of weakness in evidentiary science continue to draw attention. An influential 2009 US National Research Council report not only called for more rigorous certification of forensic experts but also for long-term research to strengthen forensic science. This insistence on improving the science used by the law is consistent with earlier research in science and technology studies (STS) noting American political culture’s special concern with maintaining science as a sphere of activity apart from contaminating contact with bias and interest—in this case, the interests of over-zealous prosecutors. These observations suggest that cross-national contrasts among reliability regimes for expert evidence hold considerable promise for researchers, as well as for those concerned with law reform and the delivery of justice.

National Science Foundation (NSF)
Division of Social and Economic Sciences (SES)
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Marjorie Zatz
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Harvard University
United States
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