Legal perceptions of science and expert knowledge

In the past half century, expert testimony has played an increasingly important role in American litigation. As the volume of expert testimony has grown, so have issues surrounding its admissibility into evidence. In the past decade, a trilogy of U.S. Supreme Court cases redefined the rules governing admissibility. This article reviews these cases and examines some of the assumptions about expert knowledge implicit in the opinions. It argues that the opinions ask judges to assume the role of scientific methodologists. Together, the 3 opinions reflect what Steven Cole calls a realist-constructivist view of science. Science is socially constructed both in the laboratory and in the wider community, but the construction is constrained by input from the empirical world.