American justice system
Uploaded by andrewsandon on Sep 20, 2006
american justice system
over the past twenty years, psychologists have conducted a great deal of research on the phenomenon of eyewitness identification. many laypersons believe that human memory works like a videocassette recorder (brigham and bothwell, 1983, p. 18). in essence, we remember what we see and can reproduce those recollections when needed. psychological studies indicate, however, that memory is really a complex process consisting of three stages: (1) acquisition, (2) retention, and (3) retrieval. in each of these stages, various factors can alter a witnesss perception of an event and render it unreliable (brigham and bothwell, 1983, p. 20).
the acquisition stage covers the witnesss perception of the original event (loftus, 1981, p. 105). factors in this stage fall into two categories: event factors and witness factors. as their names imply, these factors describe the circumstances surrounding the event and the witness, respectively. an event factor is something inherent in an incident which affects ones ability to perceive it accurately. one event factor is the duration of the event. in general, the reliability of an eyewitness identification diminishes as the viewing time decreases (loftus, 1981, p. 105). for example, the woman, who saw the robber for over thirty seconds, was in a better position to make a reliable identification than the man who saw the robber for a much shorter period of time.
a witness factor is a factor inherent in a witness which affects that persons ability to perceive (loftus, 1981, p. 110). for instance, the woman may have felt stress and fear because an unknown man accosted her on a deserted street late at night. this stress may have affected her ability to process information about the man even before he actually became outwardly violent. the effect of stress on identification depends upon the level of stress. at low levels of stress, a witness is inattentive to many details and not likely to be accurate (wells, 1988, p. 17). at moderate levels, memory improves, because a witness is better able to focus. at high levels, it becomes difficult for a person to concentrate and store the details of an event. indeed, when one is concerned with self-preservation, there is a tendency to ignore anything not necessary for survival. the retention stage spans the interval between the occurrence of the event and the recollection of information about it. accuracy in identification decreases as this interval increases (lipton, 1977, p. 90). it...