Daubert in the Juryroom: Juror Assessments of Scientific Validity and Reliability

Cuny John Jay College Of Criminal Justice, New York NY

Investigators

Abstract

Expert testimony has been a special problem in the law, and recent Supreme Court decisions have emphasized the trial court judge's role as the gatekeeper of scientific evidence and have required them to evaluate the reliability of expert evidence to determine its admissibility. If admitted, jurors have the responsibility of evaluating the influence that evidence will have in their verdict decisions. Reliability could be the means by which jurors determine if and how they will be influenced by expert testimony. Concerns have been raised about whether judges are capable of appropriately evaluating the reliability of complex expert testimony. Even if judges are able to distinguish reliable from unreliable evidence, reliability could be an issue argued by the attorneys. Therefore, reliability could be an issue for jurors to evaluate when determining the weight to give to expert testimony. Jurors also may be unable to distinguish between reliable and unreliable testimony. Unreliable testimony might not only be admitted, but it might be heavily relied upon in jurors' verdict decision making. Recognizing this potential problem, the Court suggested several legal safeguards to prevent jurors from relying on unreliable experts. These safeguards included cross-examination, jury instructions, and opposing expert testimony. The purpose of the proposed studies is to determine if jurors are sensitive to reliability, to examine the effectiveness of each of the Court's suggested safeguards, to maximize the increase in juror sensitivity to scientific reliability due to the use of these safeguards, and to provide additional information about jurors' information processing. This will be accomplished by manipulating various indicia of reliability for psychological expert testimony and by manipulating the use and type of the safeguards to determine if and to what degree their presence increases juror sensitivity to evidentiary reliability. In these studies, the type of cross-examination, jury instructions, and opposing expert testimony will be manipulated to test hypotheses regarding the interplay of safeguards and evidence reliability. These hypotheses are derived from theories about the processes underlying juror decision making based on the elaboration likelihood model and on the use of heuristics. To test these theories, complexity will be manipulated to determine when information about the reliability of expert testimony is processed peripherally or centrally. The proposed research will have a broader impact on undergraduate teaching, the college, the involvement of underrepresented groups, the research community, and on society.