Eyewitness decision -making with showups: Probative or perilous?

Showups are a technique of eyewitness identification in which a single suspect is presented to a witness for identification. Showups are controversial. Defense attorneys argue that they are suggestive and place suspects at undue risk of false identification. Prosecutors and police officers argue that showups are an indispensable investigative tool and are no more suggestive than other identification techniques. Are showups probative or perilous? If so, what can be done to improve their accuracy? This investigation converged on this question by addressing three interrelated goals. The first was to examine the effect of two system variables, retention interval and suspect clothing, on showup accuracy. The second was to determine if showups are more suggestive than lineups. The third goal was to explore carryover effects from showups to subsequent lineup identifications. ^ Eyewitness performance was evaluated with the Eyewitness Identification Paradigm. Approximately 500 undergraduate students at FIU witnesses a staged event (i.e., a "crime") in their classrooms and subsequently participated in a showup and/or lineup identification test. Half of the identification tests contained the target (i.e., the "perpetrator") and half contained a target-substitute (i.e., an "innocent suspect"). ^ The results of this study indicated that, overall, showups are not unusually prejudicial and are no more suggestive than lineups. However this study identified two specific conditions under which showups are likely to lead to false identifications of an innocent suspect. First, false identification are likely to occur in showups that are conducted shortly after a crime when the suspect is wearing clothing similar to that worn by the perpetrator. Second, placing an innocent suspect in both a showup and then a lineup substantially increases the chances that the suspect will be falsely identified in the lineup. The implications of these findings for the conduct of eyewitness investigations are discussed. ^