By Matthew Mangino
United States Supreme Court Justice William J. Brennan Jr. wrote in a dissenting opinion more than thirty years ago, “There is almost nothing more convincing than a live human being who takes the stand, points a finger at the defendant, and says, ‘That’s the one!’”
Convincing yes-- reliable, maybe not...
More than 75,000 prosecutions every year are based entirely on eyewitness identification. Some of those identifications are erroneous. The fallibility of human memory is not a new concept. In the 1800’s, memory researcher Hermann Ebbinghaus’ “Forgetting Curve” illustrated how quickly memories fade as time passes. Additionally, in 1971, England’s Criminal Law Review Committee stated that relying on eyewitness testimony could lead to false convictions. One study by University of Virginia Law School professor Brandon L. Garrett found that eyewitness misidentifications contributed to wrongful convictions in 76 percent of the cases overturned by DNA evidence.
Even U.S. Supreme Court Justice Sonia Sotomayor has acknowledged the shortcomings of eyewitness identification. She wrote, "eyewitness identifications' unique confluence of features — their unreliability, susceptibility to suggestion, powerful impact on the jury, and resistance to the ordinary tests of the adversarial process — can undermine the fairness of a trial."
Despite this, a number of trial courts have held that experts are not needed to explain eyewitness testimony. They claim that issues such as weapon focus, cross-race identification and post-event contamination are easily understood by the average juror. Jurors are then able to determine an eyewitness’ reliability without the aid of expert testimony.
Pennsylvania is one of those states. In Commonwealth v. Robinson, 5 A.3d 339 (2010), the defendant sought to offer expert testimony shedding light upon the reliability of an eyewitness in a cross-racial identification. The Superior Court held that the trial court was correct in denying the defendant’s request and properly refused to instruct the jury as to inherent difficulties in making accurate cross-racial identification.
The Court found that allowing an expert to offer an opinion that cross-racial identification is less reliable than same-race identification would improperly intrude upon the credibility determinations of the jury. The Superior Court held, in light of precedent, “we believe our supreme court would find that proposed testimony (cross-racial identification) equally objectionable.”
The Pennsylvania Supreme Court has long held that expert testimony from social scientists in the fields related to eyewitness identification — human memory, perception and recall — is improper as it intruded on the jury’s duty to judge the “credibility” of each witness.
In Commonwealth v. Benjamin Walker, 28EAP2011 the Pennsylvania Supreme Court is being asked to decide two issues: “(1) whether the trial court should have had the discretion to allow the Petitioner to present expert testimony regarding human memory, perception, and recall, and (2) whether the Court should permit expert scientific testimony, whether it be for the defense or prosecution, on how the mind works as long as the testimony has reached general acceptance”. The fundamental question before the court is the admissibility in Pennsylvania courts of expert testimony on research regarding the reliability of eyewitness identification.
According to the American Psychological Association website, two students were robbed at gunpoint early one morning. One was hit with the gun while the other got away unharmed. The injured student identified Walker as the perpetrator from a photo lineup and also at trial. The other was unable to make an identification. There were several factors that could have affected the eyewitness: poor lighting, the crime occurred quickly, the presence of a gun, and the fact that the perpetrator was of a different race than the witness. Walker’s attorneys asked the court to allow for an expert to testify about those issues. The requests were denied by the trial court. The case was argued before the Pennsylvania Supreme Court more than a year ago.
Please click here to read a response by Dr. Jonathan Vallano.
Matthew T. Mangino is of counsel with Luxenberg, Garbett, Kelly & George P.C. He is the former district attorney of Lawrence County, PA and a former member of the Pennsylvania Board of Probation and Parole. His book The Executioner’s Toll, 2010 is due out this summer. You can reach him at www.mattmangino.com and follow him on Twitter @MatthewTMangino.