'Wild cards' slash mistaken id in photo lineups

Using a "wild card" among images in a police photographic lineup dramatically lowers mistaken identification of suspects, a researcher says.

"Mistaken eyewitness identification is the leading cause of all wrongful convictions identified to date," Dr Rachel Zajac of the psychology department at Otago University told LawTalk magazine.

She has received a $170,000 grant from the Royal Society of New Zealand Marsden Fund to allow her to further investigate the technique to increase eyewitness identification accuracy.

Her early research showed that including a "wild card" in the lineup – a silhouetted head and shoulders figure with a large blue question mark superimposed – helped increase a witnesses' willingness to reject lineups that did not contain the perpetrator, she said.

"Investigators frequently obtain identification evidence by presenting the witness with a photo of their suspect placed among photos of several people known to be innocent.

"The biggest misconception about lineups is that the perpetrator will be there."

So if they were not there the witness, believing their job was to make an identification, selected the lineup member who most closely resembled the perpetrator rather than rejecting the whole lineup.

Dr Zajac tested the wild card technique with schoolchildren and found it reduced false identifications by more than a third.

She said she would use the grant to investigate issues including whether the same applied to adult witnesses, and its impact where there had been long delays before the lineups were seen.

Dr Zajac was recently involved in the New Zealand Police Review of Investigative Interviewing and was optimistic about the reception her technique would receive from investigators.

"In my experience, the police are very receptive to evidence-based ideas that would facilitate the accuracy of the evidence they solicit from witnesses."