Investigating Investigators: Examining the Impact of Eyewitness Identification Evidence on Student-Investigators

This research examined the impact of eyewitness identification decisions on student-investigators. Undergraduates played the role of police investigators and interviewed student-witnesses who had been shown either a good or poor view of the perpetrator in a videotaped crime. Based on information obtained from the witness, student-investigators then chose a suspect from a database containing information about potential suspects and rated the probability that their suspect was the culprit. Investigators then administered a photo lineup to witnesses, and re-rated the probability that their suspect was guilty. Student-investigators were highly influenced by eyewitness identification decisions, typically overestimating the information gained from the identification decision (except under conditions that led witnesses to be very accurate), and were generally unable to differentiate between accurate and inaccurate witnesses.