Baltimore police will change the way detectives have witnesses identify crime suspects, changing to a method that studies have shown to cut down on erroneous identifications.
The current practice is to show witnesses six pictures at the same time, one of whom is the target of an investigation. Under the new method, detectives will show pictures one at a time, and the person conducting the identification will not know which picture is of the suspect.
Police Commissioner Anthony W. Batts said he was considering the new method when he spoke on a law school panel in March. The department said it will provide more details on how it will work at a press event on Thursday.
The so-called "double-blind sequential" study is favored by defense lawyers and a recent field study of the technique showed that it dramatically reduced cases of mistaken identity, confirming the findings of laboratory tests. The study was conducted by the American Judicature Society, a legal reform advocacy group.
Experiments have suggested that shown a number of pictures at once, witnesses compare them and pick out the one who looks most like their memory of the suspect, even if it is the wrong choice, according to a paper summarizing the results of the field study.
And not having the detectives know the identity of the suspect prevents them from subconsciously influencing the witness, according to the paper.