Retention interval and eyewitness memory for events and personal identifying attributes.

The effect of varying the retention interval after an interaction with a stranger on the accuracy of memory for events and for personal identifying characteristics at 2 recall attempts was investigated. Although the number of correct event facts that were recalled decayed as expected, the percentage of recalled facts that were in error remained constant over time. In addition, a single recall attempt prevented further decay in the total amount correctly recalled. In contrast, although the perception of and memory for identifying characteristics varied with the attribute, retention interval had no effect on the accuracy of memory for the person, either at 1st recall or after a 2nd recall at 4 weeks. Confidence was highly predictive of the accuracy of personal descriptions. The relationship between the accuracy of witness descriptions and the probability of arresting an innocent suspect is discussed.