Eliciting person descriptions from eyewitnesses: A survey of police perceptions of eyewitness performance and reported use of interview techniques

Abstract

Techniques such as the cognitive interview (CI) have the potential to improve witness recall. Nevertheless, there is also laboratory evidence of “verbal overshadowing”; the phenomenon whereby verbally describing aspects of an event (such as the face of a perpetrator) can have negative consequences for eyewitness memory. Seventy-two UK police officers were surveyed regarding their perceptions of eyewitness performance and the methods they use to elicit person descriptions from witnesses. Factors commonly believed to influence description quality were the viewing conditions of the event, the characteristics of the witness, and their mental distress. When eliciting person descriptions there was a consensus that some components of the CI were more frequently used and believed to be more useful than others. Witnesses were generally believed to provide accurate, but incomplete person descriptions. Nevertheless, there were instances where officers reported requesting elaborative face descriptions. We propose that verbal overshadowing is unlikely to be a major concern for most police officers; however, under some circumstances its potential impact should be considered. It is also clear that it would be of benefit for future research on verbal overshadowing to examine a number of variables relevant to the forensic setting.

Notes

¹We asked police officers “In your experience, what kinds of factors impact upon the quality of witnesses’/victims’ person descriptions? For example, are there factors to do with the type of crime and the circumstances in which it was viewed or factors to do with the type of witness/victim you are interviewing that in your opinion influence the quality of person descriptions. Please mention any factors that you feel are important.” We note that the phrasing of this question may have encouraged a bias towards generating estimator as opposed to systems variables.