October 28, 2016— Joanne Yaffe, professor at the University of Utah College of Social Work—working with colleagues in law, psychology, and statistics from the University of Virginia—has been awarded a $1.3 million grant from a private foundation for a three-year project that will examine the value of eyewitness identification (EWI).
Studies estimate that between 2.3 and 5% of people currently incarcerated are actually innocent. By some estimations, the total number of people wrongfully convicted of serious crimes each year may reach 10,000. According to a report from the University of Michigan Law School’s National Registry of Exonerations, 2015 set a record for the number of wrongly convicted Americans who were either declared innocent or otherwise cleared of their convictions. Of these 149 people, many had served lengthy prison sentences, averaging some 15 years, for crimes they did not commit. While anyone can fall prey to wrongful convictions, people who are poor and from ethnic minorities are more vulnerable because they tend to have less access to resources to defend and prove their innocence. Despite the fact that black people represent only 13% of the U. S. population, they represent 63% of exonerees.
In more than 70% of wrongful conviction cases, eyewitnesses misidentified an innocent person. This misidentification may occur because of the way suspects are presented to the witness, because the witness misremembers, or because the witness perceives pressure to answer questions in a particular way. Eyewitness errors have serious consequences, both in convicting the innocent and in freeing the true culprit to commit further crimes. Scientific research on eyewitness memory has uncovered a range of reasons for deep concern in EWI reliability, but have not yet produced solutions.
Yaffe served on a National Research Council committee to examine the science related to eyewitness identification in 2013-2014. As noted in the report from that committee, Identifying the Culprit: Assessing Eyewitness Identification, research in the effectiveness of law enforcement practices for implementing eyewitness identification procedures, and the complex and interactive effects of different variables remains incomplete. This report identified potential factors that can act as moderators to increase or decrease errors in eyewitness identification and made the case for additional research these variables. The report also demonstrated that the eyewitness identification research field has not yet agreed on best practices for analyzing data or presenting results. The report concluded that evidence-informed practice and policy can proceed only after systematic reviews of research on these variables have quantified the effects of these variables and results analyzed using appropriate, comprehensive, statistical analyses to synthesize across existing studies. Further, reproducible studies may be needed to clarify previously inconclusive relationships among variables. Finally, these results need to be communicated to legal professionals and lay jurors in ways that are scientifically precise yet clear to non-scientists.
The research will address all four critical aspects of understanding and evaluating the value of EWI: (1) a comprehensive systematic review of EWI research and synthesis of findings; (2) large-scale experimental research; (3) statistical modeling; and (4) research on jury assessment, communication of EWI research in judicial settings, and legal uses of eyewitness evidence. The outcome of this research will be the assessment of accuracy of eyewitness identification under various conditions, leading to recommendations to law enforcement personnel of the optimal procedures in which eyewitness accuracy is maximized, identification of circumstances under which eyewitness identification may perform poorly, and recommendations for use of eyewitness procedures.
More specifically, the researchers will (1) conduct a more comprehensive and transparent systematic review and meta-analyses on key factors identified in prior eyewitness research; (2) conduct both lab-based and field-based large-scale studies to assess relationships among factors that can influence eyewitness accuracy; (3) produce more discerning statistical models and analytical methods for assessing eyewitness identification procedures, including the development of more precise procedures that may account for both specificity and sensitivity of eyewitness identification; and (4) conduct innovative research examining how best to convey information about eyewitness identifications to fact-finders in court, including jury instruction and expert testimony, as well as assessment of juror perceptions of eyewitness evidence and court-identifications.
The three-year project will produce practical recommendations for police professionals, attorneys, and judges. These recommendations will pertain to improved lineup practices, changes in jury instructions, and the use of both expert and eyewitness testimony in the courtroom. The research will also lead to recommendations for researchers working in the field of eyewitness identification, including more consistent methods for conducting and reporting experimental studies, improved methods of statistical analysis, and more transparent and reproducible methods for research synthesis.