Answer to Question 1
The results of various experiments on retrieval suggest that how items are encoded has a strong effect both on how, and on how well, items are retrieved. This relationship is called encoding specificitywhat is recalled depends on what is encoded. To the extent that the context under which information must be recalled is the context in which it was learned, it is helpful. To the extent that the information in learned and recalled in markedly different contexts, specificity may harm performance. This can be overcome by learning material in the context in which it will be recalled.
Answer to Question 2
Eyewitness testimony may be the most common source of wrongful convictions in the United States. The proportion of erroneous identifications has been estimated to be low as a few percent to greater than 90, but even the most conservative estimates of this proportion suggest frightening possibilities. Of the first 180 cases in the United States in which convicts were exonerated through the use of DNA evidence, more than three-quarters involved eyewitness errors.
Eyewitness testimony is often a powerful determinant of whether a jury will convict an accused person. The effect is particularly pronounced if eyewitnesses appear highly confident of their testimony. This is true even if the eyewitnesses can provide few perceptual details or offer apparently conflicting responses. In general, people are remarkably susceptible to mistakes in eyewitness testimony. They are generally prone to imagine that they have seen things they have not seen.
Loftus's eyewitness testimony experiment and other experiments have shown people's great susceptibility to distortion in eyewitness accounts. This distortion may be due, in part, to phenomena other than just constructive memory. But it does show that we easily can be led to construct a memory that is different from what really happened. Questions do not have to be suggestive to influence the accuracy of eyewitness testimony. Lineups also can lead to faulty conclusions. Eyewitnesses assume that the perpetrator is in the lineup.
Eyewitness identification is particularly weak when identifying people of a racial or ethnic group other than that of the witness. Evidence suggests that this weakness is not a problem remembering stored faces of people from other racial or ethnic groups, but rather, a problem of accurately encoding their faces. Eyewitness identification and recall also are affected by the witness's level of stress. As stress increases, the accuracy of both recall and identification declines.
Whatever may be the validity of eyewitness testimony for adults, it clearly is suspect for children. Children's recollections are particularly susceptible to distortion. Such distortion is especially likely when the children are asked leading questions, as in a courtroom setting.