The Effect of Retention Interval on the Eyewitness Identification Confidence-Accuracy Relationship

- High-confidence eyewitness identifications are widely thought to be error-prone.
- Eyewitness reliability is thought to decline following a long retention interval.
- The confidence-accuracy relationship has been measured in various ways.
- Confidence-accuracy characteristic analysis provides the most useful information.
- Using that approach, reliability is high for retention intervals as long as 9 months.

Individual researchers express a variety of views about the eyewitness confidence-accuracy relationship, but an argument could be made that the consensus view in the field is that (1) confidence is, at best, a weak indicator of accuracy, (2) the confidence-accuracy relationship becomes weaker still as the retention interval increases, and (3) eyewitnesses who express high confidence tend to be overconfident - perhaps even more so following a long retention interval. Here, we reanalyze the data from four previous retention interval studies in terms of suspect ID accuracy (Mickes, 2015). We argue that this measure is more relevant to the information sought by a court of law than either a correlation coefficient or a calibration curve (the two traditional confidence-accuracy measures). The results of our reanalysis suggest that the confidence accuracy relationship remains strong - and that high-confidence IDs remain highly accurate - even after retention intervals as long as 9 months.