Experiencing, remembering and reporting events.

Human beings frequently describe from memory events they have observed, and most people consider these descriptions to be accurate. However, scientific research on memory in the last few decades has revealed that people’s memories are often inaccurate. These errors in memory are systematic and are especially likely to occur for the kinds of events that are reported in courtroom testimony: reports of strangers performing brief, violent or unexpected acts that are frightening to the observer/witness. We examine the research on factors that affect the accuracy of initial observation, encoding and remembering and forgetting such events. We consider the special memory issues involved in describing and identifying strangers, and how these can impair the accuracy of eyewitness identifications. Throughout our review of the research findings, we consider their impact on courtroom procedures governing eyewitness testimony and identification. We conclude with a set of policy recommendations based on this scientific evidence. 1 Address for correspondence is E-Mail: haberhfc@telis.org or US-Mail: Rt 2, Box 2155 (Swall Meadows), Bishop, CA 93514. We are grateful for the comments of a large number of people who read earlier drafts of this article, and who assisted us with their thoughtful suggestions. We especially thank Gary Wells, Bruce Sales, Matthew Erdelyi, and James Whitehead for the extra time each of them gave us to help improve our presentation and logic. Introduction Most people feel they are well aware of what they can and cannot remember about the events they observe and in which they participate, and that they know about the factors that make their memory accurate. The ten statements of beliefs about memory listed below were presented by research scientists to typical people (who might become members of a jury), who were asked to indicate the strength of their agreement with the statements (usually by checking one of a number of alternatives ranging from strongly agree, agree somewhat, neither agree or disagree, disagree somewhat, to strongly disagree). The examples offered here are drawn from a number of different studies, so that not all people rated every one of the statements, although most of them were used in more than one study in exact or similar wording (for examples, see Garry, Loftus, Brown, & DuBreuil (1997), Lindsay (1994), or Loftus (1979). 1. Memory is like a video recording of your observations that can be played back at will to remind you of what you saw 2. When you are very confident about your memory for an event you observed, you are much more likely to be correct 3. Your memory is stable over time 4. Your memory for what you originally saw can be kept separate from things you learned after observing the event 5. People's faces stand out when you observe them and it is easy to remember faces, so recognition of faces is rarely in error 6. An eyewitness report is accurate evidence as to who was present and what happened 7. Having to tell the same story of what happened over and over reinforces it and makes it more resistant to change 8. When a weapon is visible during a crime, witnesses are more accurate in remembering the details of the crime. 9. Personally experienced traumatic events are remembered more accurately than everyday ones. 10. Observed violent events are remembered more accurately than everyday events. Most people (in some cases nearly all of them) who have been asked agree or strongly agree with these ten statements. This finding provides a benchmark to use when considering what a typical juror might believe about how memory functions. In contrast, when these statements are judged by memory experts—scientists whose profession is providing empirical demonstrations of how human memory actually functions—the majority of memory experts disagrees with each statement. (Some of the recent scientific descriptions of memory functioning can be found in Loftus, 1979; Ross, Read & Toglio, 1994; Rubin, 1996; Sporer, Malpass & Koehnken, 1996; and Davies, Ellis & Shepherd, 1981.) Further, as we will show in this article, these experts are right: there is sound scientific evidence showing that each of these statements is contradicted by the facts. Now consider the following description of a bank robbery, drawn from actual cases. Several men entered a bank, tied up the only guard in the lobby, told the customers to lie down on the floor, and demanded that the tellers hand over all their money. The robbers then left. There were five tellers, two officers, one guard, and five customers in the bank at the time. When the police took their statements over the next hour, there was little consensus among the 13 witnesses as to the number of robbers, what they looked like, what they did, the presence of weapons, or the duration of the robbery.