Date of Award


Document Type


Degree Name

Master of Arts (MA)



Committee Chair

Jeffrey Neuschatz

Committee Member

Aurora Torres

Committee Member

Jodi Price


Judicial error., Visual perception., Criminal investigation., Witnesses--Psychology., Eyewitness identification., Forensic psychology.


Showups (one-person identifications) have been declared less reliable than traditional lineups (six person group identifications) by the US Supreme Court and social science researchers. A 2 (Perpetrator: Absent vs. Present) x 2 (Retention Interval: Immediate versus Delayed) x 4 (showups, fair lineups, biased lineups, police lineups) between subjects factorial design was employed to determine differences in identification accuracy in each condition. Participants (N = 584) viewed a mock crime video, and then proceeded (immediately or 2 days later) to an identification task. We predicted retention interval to interact with type of identification procedure. Specifically, immediate showups were expected to perform better than delayed lineups. Probative Value (PV) measures and Receiver Operating Characteristic (ROC) curves were utilized to analyze and compare the data. Overall, showups - even if conducted immediately-- were not a reliable procedure. The suggestiveness of showups appears to outweigh any benefits they have for police.



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