ABSTRACT
The expert testimony is introduced by the defense in criminal cases involving eyewitness identifications of a defendant by one or more prosecution witnesses. In such cases the expert typically testifies about the general unreliability of human perception and memory and points to specific factors present in the case that may contribute to inaccurate eyewitness identifications. Expert psychological testimony on eyewitness performance has generated substantial controversy among psychologists. Correctly perceiving the expert’s role to be that of attacking the credibility of eyewitnesses, judges frequently rebuffed the efforts of defense attorneys to introduce eyewitness experts. Advocates of expert testimony on eyewitness performance argue that the testimony does in fact assist the jury. A common claim of experts testifying about eyewitness behavior is that the stress experienced by a witness to a crime impairs the ability of the witness to encode and later remember information about the crime and the perpetrator.
