Line-up witnesses ‘pick people they dislike’

Witnesses may point the finger at a suspect in a line-up simply because they do not like the way they look, scientists said.

Psychologists Hartmut Blank and Jim Sauer, of the University of Portsmouth, have been awarded £100,000 to examine what may influence people when picking out a possible perpetrator in an identification parade.

Their initial research suggests that people are more likely to identify line-up members they dislike and less likely to identify someone they like.

They say that such decisions are automatic and spontaneous rather than thought out.

Dr Blank, a specialist in memory and the effect of social influences on how and what we remember, said: “It’s natural that we don’t enjoy creating trouble for someone we like by identifying them as a perpetrator.

“The feeling of liking can definitely influence judgment.

“The liking bias is a subtle effect though otherwise the justice system would have long been aware of it.”

Dr Sauer said that this “liking bias” might be behind a growing number of documented cases in which mistaken identifications contributed to the convictions of people who were later proved innocent through DNA testing.

He said: “The legal system finds eyewitness identification evidence compelling but it has contributed to many wrongful convictions over the years.

“Eyewitness error represents a significant cost to society and criminal justice system.

“The first cost is an innocent person is jailed, the second cost is once an individual has been identified, police investigations may narrow, so the perpetrator remains at large.

“Most people think their memories are reliable but no-one is exempt from vulnerability to bias.