Most Similar is Different: Response Bias in Lineups

Abstract

Previous research has shown that distractor faces made up of features of previously seen target faces are more likely to be selected as targets than the targets themselves. The present experiments sought to determine whether there is a tendency to pick a face out of a lineup if the face is more similar to the other lineup members than they are to each other. In Experiment 1, 25 subjects ranked members of lineups on similarity to target faces. The important comparisons were between rankings of the faces similar to the distractors (the critical faces), target faces, and other distractors. When the target faces were present in the lineup, no significant difference between rankings of the targets and the critical faces was found. When no targets were present in the lineup the critical faces were judged to be more like the targets than were the other distractors. This latter finding was replicated in Experiment 2 using visual stimuli other than faces. Implications for choosing police lineups are discussed.