ABSTRACT
The purpose of the research discussed in this article was to study the effect of instructions on subjects’ evaluation of eyewitness identification evidence. One hundred seventy-seven law students were administered surveys that summarized evidence presented at two criminal trials. Critical inculpatory evidence in both cases included eyewitness identifications. The independent variable was the instructions. Subjects were directed to read the evidence and instructions and to indicate their verdict of guilty or not guilty. Survey variations included different instructions concerning proper evaluation of identification evidence. Results indicate that the particularized cautionary instruction used in a number of federal courts increased conviction rates for both cases as compared to subjects to whom a short burden of proving identity instruction was administered. (P > .05.) Results further suggest that the particularized instruction increased the conviction rate for the “violent” case and decreased the conviction rate for the “nonviolent” case as compared to subjects to whom no identification instruction was administered. The results conflict with assumptions made by courts and scholars that the particularized instruction reduces the conviction rate. Implications for jury instructions and the benefits of expert psychological testimony are discussed.
