Sequential Lineups Are More Accurate, According to Ground-breaking Report on Eyewitness Identification Procedures
(Des Moines, IA – September 19, 2011) – A highly-anticipated field study on eyewitness identification procedures has found that double-blind sequential lineups – lineups where the administering officer doesn’t know which person is the suspect and the witness views one suspect photograph at a time – produce fewer mistaken identifications than lineup procedures that present all of the suspect photographs at once or simultaneously. The study also found that double-blind sequential lineups as administered by police departments across the country resulted in the same number of suspect identifications but fewer known-innocent filler identifications than double blind simultaneous lineups. A report, issued by the American Judicature Society, comes on the heels of a landmark decision by the New Jersey Supreme Court mandating major changes in the way courts evaluate eyewitness identification evidence (see link to the full report on page 2).
The report, “A Test of Simultaneous vs. Sequential Lineup Methods: An Initial Report of the AJS National Eyewitness Identification Field Studies,” has implications for reducing wrongful convictions in the United States criminal justice system. Eyewitness misidentification is the single greatest cause of wrongful convictions nationwide, playing a role in more than 75% of the 273 convictions overturned through DNA testing.
“The beauty of this study is it’s the first time we’ve seen social scientists, prosecutors, criminal defense attorneys, and the law enforcement community come together to test new ways to improve the reliability and credibility of eyewitness evidence,” said Dr. Gary L. Wells, director of social sciences for the American Judicature Society (AJS) Center of Forensic Science and Public Policy. “And now we have proof from the field that witnesses who view double-blind sequential lineups are just as likely to pick the suspect, and perhaps more importantly, less likely to make a misidentification by picking a filler in the lineup.” Wells is the principal investigator of the field study and is an internationally-renowned eyewitness identification researcher at Iowa State University in Ames.
AJS, in collaboration with the Police Foundation, the Innocence Project, and the Center for Problem-Oriented Policing, implemented a national field study at four law enforcement agencies to determine which lineup method – sequential or simultaneous – is more accurate. The study was designed to correct some of the problems in a 2006 Illinois study that was later found to have flawed methodology. Unlike the Illinois study that attempted to compare double-blind sequential lineups to non-blind simultaneous lineups, all of the lineups in the AJS study were conducted double-blind, meaning the officer administering the lineup did not know the suspect’s identity and the witness was told that the officer didn’t know. The Austin (TX) Police Department; Tucson (AZ); the San Diego (CA); and Charlotte-Mecklenburg (NC) police departments participated in this research, called the “AJS National Eyewitness Identification (EWID) Field Studies.
“Drawing on an unusually rich body of research from experimental psychologists, we have the tools to reduce eyewitness error, to protect the innocent and help law enforcement apprehend the guilty,” said Barry Scheck, co-director of the Innocence Project, which is affiliated with Cardozo School of Law. “This scientifically rigorous field study is a model for how that can be done practically, systematically and transparently.”
Rosemary Lehmberg, Travis County (TX) District Attorney, added, "My office has worked for years to make sure no innocent person is ever wrongfully convicted. This groundbreaking study demonstrates state-of- the- art methods that will dramatically reduce the risk of mistaken identifications, which is the leading cause of wrongful incarcerations. It is a major step forward and I am proud to have participated."
The AJS National EWID Field Studies were conducted between 2008 and 2011 using a specially-designed software application created by SunGard Public Sector, Inc. The software application was uploaded onto laptop computers and ensured that: instructions were consistently administered at the start of each lineup; the lineup condition (sequential or simultaneous) was randomly applied; and the order of mug shot photographs was randomized prior to the witness beginning the procedure. The computer-based photographic lineups included one suspect photo and five known-innocent filler photos. As is the practice by police departments that use the double-blind sequential method, witnesses viewing a sequential lineup were allowed to see the photographs a second time if they asked.
Although hundreds of controlled laboratory studies have consistently found that sequential lineup procedures result in a substantial reduction of mistaken identifications, many police departments have been hesitant to change their procedures based on laboratory findings alone. Critics of the sequential method argue that any loss in accurate identifications is too costly and that lab studies cannot be as easily applied to real-world scenarios. Today’s findings, which were based on real-world experiences in four separate jurisdictions, show these arguments to be unfounded.
While resistance to adopting these best practices remains, New Jersey and North Carolina require double-blind sequential lineups statewide and many jurisdictions do as well, including Santa Clara County, CA, Denver, CO, Boston, MA, and Dallas, TX. The experiences of these jurisdictions resolutely demonstrate the benefits and feasibility of adopting eyewitness identification reforms.
While the research results indicate sequential lineups produce fewer mistaken identifications, Wells notes: “Sequential presentation is not a silver bullet for the mistaken identification problem, but can lead to fewer innocent suspects being misidentified when the lineups are conducted double blind.”
The Police Foundation is conducting a second phase of the AJS National EWID Field Studies to evaluate the cases captured during data collection and assess whether lineup presentation methods have an impact on witnesses’ accuracy and ability to identify the actual perpetrators. An important difference between laboratory studies and actual criminal cases is that the identity of the perpetrator is not necessarily known in the actual criminal cases. While a witness may identify the suspect in an actual lineup, it cannot be presumed that the suspect is the guilty person. The Police Foundation is expected to release a report on the second phase of the AJS National EWID Field Studies in 2012.
In the coming months, lead scientists Drs. Gary L. Wells, Nancy K. Steblay (Augsburg College, MN), and Jennifer E. Dysart (John Jay College of Criminal Justice, NY) plan to continue their analysis of data gathered during the field studies, such as the witnesses’ certainty, cross-race comparisons, lighting conditions, and the presence or absence of a weapon at the time of the crime.
The AJS National Eyewitness Identification Field Studies are supported by grants from the Open Society Foundations, the Laura and John Arnold Foundation, and the JEHT Foundation.
Read the full report here.
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