This section examines some practical applications of memory research. There are two experiments, one concerning accuracy of recall and one concerning police lineup identification.
Our legal system relies heavily on eyewitness testimony, despite a large body of evidence that such recollections are often unreliable. A number of problems are known, ranging from distraction and lack of information during a disturbing event to social pressures and the emotional state of the witness. The two experiments you did address errors that can inadvertently result from standard police procedures.
Elizabeth Loftus has studied many aspects of memory and has often testified as an expert witness (see Loftus and Ketcham, 1991, for an engaging account of her experiences). replicates part of a study of the effect of leading questions (Loftus, 1975), using her original set of slides. If you did version A, you were given a leading question that might bias your later identification of a scene (identifying a stop sign rather than a yield sign). If you did version B, you were given a different leading question, which might make you mistakenly recognize a photograph of the victim standing in the crosswalk. Not everyone makes mistakes after leading questions, but when such tests are given to large groups, errors are common in those experiencing leading questions.
Gary Wells and his colleagues have done many experiments examining the procedures by which witnesses identify suspects, ranging from artists’ renditions of suspects to the use of the standard police lineup and potentially biasing feedback given by police to witnesses. Their work has resulted in a set of recommendations (Wells et al., 1998) that have been implemented in some states. One major recommendation is that police use sequential rather than simultaneous lineups (Wells, 1984; Lindsay and Wells, 1985). showed why. If you did version A, you were given the standard simultaneous lineup. While you may not have mistakenly identified a suspect, large studies show that mistaken identity is more likely with a simultaneous lineup than a sequential lineup. Version B used a sequential lineup. To see what the other type of lineup is like, you may want to try the experiment that you did not do.
There are many publications about eyewitness research. In addition to the book by Loftus and Ketcham, there are review articles by Wells and others (Wells et al., 2000; Wells and Olson, 2003). Many of the recommendations made by Wells and others have met with resistance from police departments. It is not clear whether this is due to inertia, distrust of academia, or a feeling that it is better to risk charging an innocent person than to risk releasing a criminal.
Photos in the recall test were provided by Elizabeth Loftus of the University of California at Irvine, who retains copyright. Video and pictures used in the lineup test were provided by Gary Wells of Iowa State University, who retains copyright.