Lay (mis)perceptions of suspect-identification accuracy from biased and unbiased lineups.

Abstract

Suspect identifications from unbiased lineups (fair lineups) are more accurate than suspect identifications from biased lineups (Wixted & Wells, 2017). We examined whether laypersons were sensitive to the fact that suspect-identification accuracy is higher for unbiased than for biased lineups. Laypersons were presented with biased and unbiased lineups, told who the witness identified, and asked to rate the likely accuracy of the identification. Over the course of nine experiments (N = 1,851), laypersons demonstrated a robust biased-lineup preference effect, in which they incorrectly judged suspect-identification accuracy as higher for biased than for unbiased lineups. This effect occurred even though laypersons were sensitive to lineup fairness and persisted even when participants were provided with the type of information needed to understand how lineups work. The biased-lineup preference effect was eliminated—but not reversed—when participants were (a) primed to rate lineup fairness prior to assessing suspect-identification accuracy and (b) provided with a comprehensive narrative explanation of how lineups work. Preference for the unbiased lineup emerged only when participants were explicitly told that accuracy was higher for unbiased lineups. Laypersons showed limited ability to reason correctly about suspect-identification accuracy from biased and unbiased lineups.