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Juror Decision Making in Eyewitness Identification Cases

NCJ Number
Law and Human Behavior Volume: 12 Issue: 1 Dated: (March 1988) Pages: 41-55
Date Published
15 pages
This study examines the layperson's knowledge of the factors that influence eyewitness memory by evaluating the manner in which mock jurors integrated eyewitness evidence to draw inferences about defendant culpability and the likelihood that an identification was correct.
A total of 321 undergraduate college students viewed a videotaped trial within which 10 witness and identification factors were manipulated between trials. The two primary dependent measures were verdict and the subject's ratings of the probability that the identification was correct. The 10 witness and identification factors were robber disguise, weapon visibility, violence, retention interval, mugshot search, lineup instructions, lineup size, similarity of lineup members, voice samples, and witness confidence. Manipulation checks showed the subjects demonstrated superior memory for the evidence, and the manipulated variables had their intended impact on appropriate rating scales. Only one variable, witness confidence, however, had reliable effects on subjects' perceptions of culpability, on the perceived likelihood that the identification was correct, and on several other relevant dependent variables. Eight variables that have been shown to affect identification accuracy in the empirical literature had trivial effects on mock jurors' inferences. Findings indicate that laypersons are insensitive to the factors that influence eyewitness memory. 1 table and 36 references. (Author abstract modified)

Date Published: January 1, 1988