Eyewitness Identification Field Studies

Mistaken eyewitness identification is the leading cause of wrongful conviction of innocent people in the United States.  In the more than 230 post-conviction DNA exonerations that have occurred in the United States since 1989, inaccurate eyewitness testimony contributed to wrongful convictions in over 75% of those cases. 

Since the mid-1970's, experimental psychologists have studied the psychological processes involved in eyewitness memory and factors affecting the reliability of eyewitness identification. Recommended procedures reforms have been identified to improve the accuracy of eyewitness identification, including: 

·          Double-blind administration: The person administering the lineup does not know which individual is the suspect;

·          Cautionary instructions: Prior to viewing the lineup, the witness is instructed that the perpetrator may or may not be in the lineup, that the witness need not make an identification, and that the administrator does not know which individual is the suspect;

·          Lineup composition and filler selection: Persons, other than the suspect, participating in the lineup fit the general descriptions of the perpetrator and the suspect does not unduly stand out from the non-suspect fillers;

·          Confidence statement: Immediately after an identification is made, the witness is asked to describe his/her certainty in making the identifications.

·          Sequential lineup presentation:  Lineup photographs are shown one at a time, rather than all at once.

In 2005-2006, a field study conducted in Illinois tested double-blind sequential procedures versus traditional simultaneous procedures.  While its methodology has been widely criticized and the validity of its results questioned, the Illinois study raised questions concerning the effectiveness of sequential procedures.  

In September 2006 a meeting in Greensboro, NC, brought together nationally prominent eyewitness experts to discuss and outline proper designs and protocols for conducting additional field experiments on this issue.  The purpose of the study is to evaluate the effectiveness of simultaneous versus sequential line-ups in identifying perpetrators using computer-based lineup procedures in actual police investigations.  The research and lineup procedures developed are generally referred to as the "Greensboro Protocols".

Working in collaboration with law enforcement, prosecutors, and defense attorneys, to increase accountability, standards and scientific methodology in criminal investigation, the study will be implemented at four sites across the nation.  The first two sites to participate in the EWID Field Studies are the Charlotte-Mecklenburg (NC) Police Department and the Tucson (AZ) Police Department. Two additional sites will be announced upon selection.   

The primary variable being tested in the EWID Field Studies is sequential versus simultaneous presentation of photo lineups under double-blind administration (in which the lineup administrator is not aware of the identity of the suspect).  A specially-designed proprietary software program will enable scientists to examine the primary research question and improve the accuracy of data collection. In addition, the program will allow witnesses to self-administer the photo lineup using laptop computer. 

The EWID Field Studies will be administered in two separate, but equally important phases.  During the first phase of the EWID Field Studies, administered by the American Judicature Society, scientists will gather and analyze data from approximately 1,200 actual eyewitness identifications.  The Police Foundation will lead the second phase, in which relative evidentiary strength of all cases captured in the first phase will be evaluated to assess whether the presentation methods used in photo lineups have an impact on witnesses’ accuracy and ability to identify actual perpetrators in a lineup. 

The EWID Field Studies are led by Dr. Gary L. Wells, Distinguished Professor at Iowa State University and Director of Social Sciences for the AJS Institute.  Other scientists involved in the Study include: Dr. Brian L. Cutler (University of Ontario Institute of Technology), Dr. Nancy K. Steblay (Augsburg College), Dr. Jennifer Dysart (John Jay College of Criminal Justice-CUNY).