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Holistic Facial Composite Creation and Subsequent Video Line-up Eyewitness Identification Paradigm
Published on: December 24, 2015
Sequential lineup laps and eyewitness accuracy
Nancy K Steblay1, Hannah L Dietrich, Shannon L Ryan
1Department of Psychology, Augsburg College, Campus Box 32, 2211 Riverside Avenue, Minneapolis, MN, 55454, USA. steblay@augsburg.edu
Law and Human Behavior
|July 16, 2010
Summary
Repeated viewings of sequential lineups increase witness errors when identifying strangers. A single viewing is more accurate than double viewings for lineup diagnosticity.
Area of Science:
- Forensic Psychology
- Eyewitness Identification Procedures
Background:
- Double-blind sequential lineups are standard police practice.
- The efficacy of repeated viewings (laps) of sequential lineups is under investigation.
Purpose of the Study:
- To determine the impact of repeated viewings on witness accuracy in sequential lineups.
- To assess lineup diagnosticity with single versus double laps.
Main Methods:
- Two laboratory experiments were conducted.
- Participants viewed sequential lineups, with variations in the number of laps allowed/required.
Main Results:
- A sequential lap effect was observed: increased picks from the first to second lap for stranger culprits.
- The second lap yielded more identification errors than correct identifications.
- Lineup diagnosticity was higher for single-lap procedures compared to double-lap procedures.
- Witnesses viewing a second lap made more errors than those viewing one lap or those required to view two laps.
- Witnesses with prior culprit exposure did not show a sequential lap effect.
Conclusions:
- Repeated viewings of sequential lineups can decrease identification accuracy, particularly for stranger culprits.
- Single-lap sequential lineups demonstrate higher diagnosticity than double-lap procedures.
- Police should consider limiting viewings in sequential lineups to enhance accuracy.
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