The dismissal of the Duke rape case is all over the news, but it’s particularly interesting that in almost every report, the attorney general is on record blasting the unreliable eyewitness procedures as a primary cause of the unfounded charges against the Duke athletes.
As was reported some months ago, the ID procedures in the case involved a photo lineup comprised only of Duke lacrosse players — in other words, an all-suspect lineup. As leading psychologists like Gary Wells have been saying for years, including only one suspect in a lineup is crucial to a reliable ID procedure. In fact, in his 2005 article titled “Eyewitness Identification: Systemic Reforms” (PDF), Wells listed the inclusion of only one suspect per lineup as number one in his list of six recommended reforms to increase the reliability of police lineups:
A lineup that contains only suspects (no fillers) is like a multiple-choice test with no “wrong” answer. In an all-suspect lineup, charges may be brought against anyone whom the suspect identifies. If there are fillers, however, an eyewitness who is prone to simply pick someone is likely to pick a filler. Because it is known that the identification of a filler is a mistake, charges will not be brought against a filler and the unreliability of the witness is revealed.
A properly conducted eyewitness identification procedure should serve as an objective test of the witness’s memory of the identity of the perpetrator or perpetrators. When there are no fillers, as in the Duke case, the procedure gives no insight into what should be the essential question — namely, does the witness recall the identity of the person who committed the crime?