Police lineups of the future?

Problems associated with eyewitness identification decisions have long been highlighted by memory researchers (e.g., Loftus, 1979), with overwhelming evidence that witnesses can err, sometimes with disastrous consequences. Guided by the rationale that witnesses have access to potentially probative memorial information not captured by the traditional categorical lineup responses, an alternative procedure was examined in 6 experiments with adult (N = 1,669) and child (N = 273) witnesses. Instead of witnesses being asked to identify the offender from the lineup, they rated their confidence in the match between the offender and each lineup member and then variations in the maximum (max) confidence values assigned (i.e., the highest rated lineup members) were examined. Specifically, we evaluated how well max confidence values predicted suspect guilt or innocence. When suspects (guilty or innocent) in a lineup received the max confidence rating, the probability of guilt increased with the max. When the suspect received a rating lower than the max, they were generally more likely to be innocent. Max confidence patterns also predicted guilt where a traditional positive identification would have been unlikely: for example, when the max was low, when the witness gave the max to multiple lineup members, or when a filler received the max but the suspect also received a high rating. The data indicate that witnesses have access to probative memorial information often not captured by the traditional lineup responses when identifying someone or rejecting the lineup. Guidelines for the use and interpretation of this theoretically informed futuristic alternative to existing lineup procedures are provided.