NCJ Number
249006
Date Published
January 2012
Length
92 pages
Annotation
The overall objective of this study was to improve the quality and probative value of evidence obtained from eyewitnesses through police lineup procedures.
Abstract
A sequential lineup of individuals was found to produce more accurate eyewitness suspect identifications from lineups than a simultaneous lineup of a group of individuals. In addition, new laboratory data obtained in this study found an improvement in eyewitness identification accuracy by giving eyewitnesses the option for a "not-sure" response option. Giving eyewitnesses the instruction that a suspect's appearance may have been changed had minimal impact on the accuracy of suspect identifications. A significant negative outcome resulted from exposing eyewitnesses to repeated lineups. The study conducted an updated meta-analytic review of research that compared simultaneous to sequential lineup formats. An evaluation was conducted of the sequential superiority effects, and factors that moderate this effect are explained. Controlled laboratory testing was conducted of the impact on eyewitness accuracy of three individual lineup procedural components: relaxation fo the "Yes/No" response requirement of the sequential lineup procedure to allow for "I'm not sure" responses, an appearance-change instruction to eyewitnesses, and the use of multiple identification tasks with the same witness. The study also collected and analyzed data in collaboration with the Tucson Police Department (Arizona) in comparing performance on lineup identification under double-blind simultaneous versus double-blind sequential line-up procedures. 7 tables and 59 references
Date Published: January 1, 2012