The U.S. Supreme Court recently considered Perry v. New Hampshire, a case questioning the validity of eyewitness testimony when the identification was made under unreliable circumstances. At the same time, years of scientific study on the accuracy of human memory are pointing to the need for reform in the use of eyewitness evidence in criminal cases. Barbara Tversky, a psychology professor at Columbia University, whose experiments on memory were reported in the journal Cognitive Psychology, noted, “Memory is weak in eyewitness situations because it’s overloaded. An event happens so fast, and when the police question you, you probably weren’t concentrating on the details they’re asking about.” About 75% of DNA-based exonerations have come in cases where eyewitnesses have made mistakes. Scientists suggest that witness testimony should be viewed more like trace evidence, with the same fragility and vulnerability to contamination. Strong emotions felt by victims of a crime is one such possible area of contamination. Gary Wells, a psychology professor at Iowa State University, found that the accuracy of lineups improves when the possible suspects are presented to witnesses in sequence, rather than all at once, as in the traditional lineup. The downfall of side-by-side lineups, Dr. Wells said, is that “if the real perpetrator is not in there, there is still someone who looks more like him than the others.” The Supreme Court of New Jersey recently promulgated new rules for dealing with the problems of eyewitness identification.