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Identification Parades - How Important Is Delay?

NCJ Number
Home Office Research Bulletin Issue: 11 Dated: (1981) Pages: 14-17
J W Shepherd; G M Davies; H D Ellis
Date Published
This article reports on several experiments undertaken by the London Home Office to assess the reliability of witness identification of subjects involved in incidents and to determine if that reliability is impaired by increasing delays before identification questioning.
Several kinds of experiments were made to test identification reliability. One was conducted to test whether a photographic parade or a video taped parade would have different identification rates than a live parade and found no differences in identification rates among the three types. Another attempted to determine if photographic searches or verbal descriptions of the target had any effect on identification for a witness who has seen the subject and later inspects a series of photographs which do not contain the target. This involved delays of 1 and 4 months. It was found that neither the photograph search, nor the verbal description, nor the length of delay had any effect on identification rates. However, the target for this experiment was not in the photographs. Other research has shown that a stand-in on the parade whose photograph appears in the mug-shot series is identified as the culprit as often as the real target. A third experiment, concerned with whether an incident involving two targets would result in different identification rates and misidentification rates when the parades had both, only one, or none of the targets present, showed that putting both targets on a parade did not improve the identification rate. Misidentification rates did not vary according to the number of targets on parade, and the length of delays (1 to 4 months) had no effect on identification rates. A final experiment tested identification rates and times of delay and found little difference in rates for 1-month and 3-month intervals, but an expected sharp drop in a 1-year interval. Nine references are included.


Length: 4 pages
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