SCIENTIFIC EXPERT TESTIMONY AND INTELLECTUAL DUE-PROCESS

Scientific information is relevant to, even decisively important in, a rapidly growing percentage of civil and criminal cases. Most judges a nd juries however lack the background necessary to make independent ju dgments about scientific evidence. Thus, they solicit and defer to the opinions of expert scientific witnesses. In this Article, Professor B rewer explores and models the reasoning process that judges and juries use in assessing these witnesses' testimony. Almost inevitably finder s of fact and law alike are presented, not with a univocal authoritati ve voice of scientific truth, but instead with competing scientific ex pert witnesses who testify to contrary or even contradictory scientifi c propositions. To resolve such inconsistencies, judges and juries rel y on such indicia of expertise as credentials, reputation, and demeano r. Drawing on work in jurisprudence, philosophy of science, and episte mology, as well as on doctrines and leading cases on scientific eviden ce, the Article shows that in many cases such reliance yields epistemi cally arbitrary judgments. This outcome violates an emerging norm, a n orm Professor Brewer calls ''intellectual due process.'' This norm, th e Article shows, is immanent in values to which many legal systems, in cluding those of the United States, are already committed. Moreover it places important epistemic constraints on the reasoning process by wh ich legal decisionmakers apply laws to individual litigants. The Artic le thus concludes with some brief observations about the kinds of doct rinal and institutional reforms that might better enable a legal syste m to meet the high aspirations of intellectual due process.