Loftus, E. F. (1980). Impact of expert psychological testimony on the unreliability of eyewitness identification. Journal of Applied Psychology, 65, 9-15.
Studied the influence on jurors of expert testimony about eyewitness identification. In Exp I, 240 university students (all registered voters) acted as jurors and received evidence against a defendant in a violent or a nonviolent case. The major piece of prosecution evidence was the testimony of the eyewitness. Half of the Ss read about the testimony of a defense expert on the reliability of eyewitness identification, whereas half did not. Individual verdicts were reached. The results indicate that there were fewer convictions when expert testimony was permitted. In Exp II, 120 students received evidence in a hypothetical violent crime and then deliberated in juries of 6 to reach a verdict for or against the defendant. Ss who had read about the expert testimony spent much more time discussing the eyewitness account than did Ss who had not been presented with expert testimony. Results indicate that one consequence of presenting psychological expert testimony is an increase in the amount of attention that jurors give to eyewitness accounts, perhaps enhancing their scrutinization. Juries hearing expert testimony on eyewitness reliability convicted less often and discussed eyewitness testimony more than juries not exposed to expert testimony.