Double exposure: The effects of repeated identification lineups on eyewitness accuracy

摘要

Eyewitnesses may be asked to identify the same suspect from a lineup on successive occasions. This study explored the effects on eyewitness decisions of repeated same-suspect lineups, within a 2×2×2 mixed-model factorial design. Witnesses to a video crime attempted to identify the culprit from two same-format lineups (simultaneous or sequential) separated by a 2-week retention interval (Lineup1, Lineup2) in which a suspect (guilty or innocent) was common to the lineups. We predicted two components of a posited repeated lineup effect: that positive identification errors made at the first lineup would be carried forward rather than corrected at the second lineup and that the number of false identifications of the innocent suspect would rise from first to second lineup. Predictions were supported, with a stronger negative impact of repeated lineups for simultaneous than sequential lineups. Additionally, witnesses who made selections of the guilty suspect and of the innocent suspect at Lineup2 were equally confident and were significantly more confident than witnesses who declined to pick. The results underscore concerns about possible negative outcomes from repeated lineups.