Biomedical subjects

Gary L Wells

Publications and source records attributed to Gary L Wells.

4 recordsLinked to original sources

PubMed2003

Distorted retrospective eyewitness reports as functions of feedback and delay.

Participant-witnesses viewed a crime video and attempted to identify the culprit from a culprit-absent lineup. The 253 mistaken-identification eyewitnesses were randomly given confirming, disconfirming, or no feedback regarding their identifications. Feedback was immediate or delayed 48 hr, and measures were immediate or delayed 48 hr. Confirming, but not disconfirming, feedback led to distortions of eyewitnesses' recalled confidence, amount of attention paid during witnessing, goodness of view, ability to make out facial details, length of time to identification, and other measures related to the witnessing experience. Unexpectedly, neither delaying the measures nor delaying feedback for 48 hr moderated these effects. The results underscore the need for double-blind lineups and neutral assessments of eyewitnesses' certainty and other judgments prior to feedback.

Attention↗

PubMed2002

Eyewitness testimony.

The criminal justice system relies heavily on eyewitness identification for investigating and prosecuting crimes. Psychology has built the only scientific literature on eyewitness identification and has warned the justice system of problems with eyewitness identification evidence. Recent DNA exoneration cases have corroborated the warnings of eyewitness identification researchers by showing that mistaken eyewitness identification was the largest single factor contributing to the conviction of these innocent people. We review major developments in the experimental literature concerning the way that various factors relate to the accuracy of eyewitness identification. These factors include characteristics of the witness, characteristics of the witnessed event, characteristics of testimony, lineup content, lineup instructions, and methods of testing. Problems with the literature are noted with respect to both the relative paucity of theory and the scarcity of base-rate information from actual cases.

Criminal Law↗

PubMed2002

The damaging effect of confirming feedback on the relation between eyewitness certainty and identification accuracy.

The authors investigated eyewitnesses' retrospective certainty (see G. L. Wells & A. L. Bradfield, 1999). The authors hypothesized that extemal influence from the lineup administrator would damage the certainty-accuracy relation by inflating the retrospective certainty of inaccurate eyewitnesses more than that of accurate eyewitnesses (N = 245). Two variables were manipulated: eyewitness accuracy (through the presence or absence of the culprit in the lineup) and feedback (confirming vs. control). Confirming feedback inflated retrospective certainty more for inaccurate eyewitnesses than for accurate eyewitnesses, significantly reducing the certainty-accuracy relation (from r = .58 in the control condition to r = .37 in the confirming feedback condition). Double-blind testing is recommended for lineups to prevent these external influences on eyewitnesses.

Adolescent↗

PubMed2002

Eyewitness identification: information gain from incriminating and exonerating behaviors.

An information-gain approach to the analysis and interpretation of eyewitness identification data is described. The information-gain analysis is grounded in Bayesian statistics, permitting the important role of prior probabilities to be explored. This approach also forces a more complete treatment of the data and reveals important patterns that have escaped previous attention in the eyewitness identification literature. Particularly important is the ability of information-gain analyses to make salient the exonerating value of eyewitness behaviors rather than just their incriminating value. Analyses of sample data sets show how the exonerating value of filler identifications and "not there" responses can actually exceed the incriminating value of identifications of the suspect at certain points in the distribution of prior probabilities.

Attention↗