Improving Eyewitness Identification Accuracy with a Modified Lineup Procedure

Abstract

The purpose of the current program of research was to examine whether a modified lineup procedure would increase identification accuracy. Study 1 (N = 241) examined several lineup procedures including the simultaneous, sequential, and elimination lineup along with a new procedure known as the elimination-plus. The elimination-plus lineup had participants provide a confidence measure following their first decision. In target-present lineups, the elimination-plus procedure was the only procedure to significantly predict accuracy. Judgment one confidence significantly predicted identification accuracy; once a witness was 75% or more confident in his or her decision, making a correct decision rose above chance level. Similar results were found for judgment two such that once a witness was 75% or more confident, making a correct decision rose above chance level. Given that there are two confidence ratings in the elimination-plus procedure, the two ratings were averaged to determine whether it was predictive of accuracy. Similar to the confidence obtained at judgment one and judgment two, once a witness had an average of 75% confidence, making a correct decision rose above chance level. Study 2 (N = 120) examined whether modifications to the existing elimination lineup procedure instructions would increase the rate of correct identification in target-present lineups. No significant differences were found; however, participants’ decision criteria became more conservative such that both the rate of correct identification in target-present lineups and the rate of false positive identifications in target-absent lineups increased. Study 3 (N = 240) examined whether adding a salient rejection option to judgment two of the elimination lineup procedure would increase identification accuracy. Contrary to prediction, the salient rejection option was detrimental to identification accuracy in target-present lineups with no benefit to target-absent decisions. Overall, results suggest that adding in confidence following judgment one of the elimination lineup procedure is a beneficial modification as it provides another piece of evidence as to the guilt of the suspect. Given that confidence has been recognized by the Supreme Court of the United States in Neil v. Biggers (1972), these results shed light on a novel way of examining identification accuracy.