Older people are more likely to make mistakes in identifying suspects in police line-ups.

This is the finding of research by Dr Helen Kaye of The Open University to be presented at the British Psychological Society annual conference, 7 May 2014, at the International Convention Centre in Birmingham.

Some 134 people (aged 22 to 66 years old) watched video footage of a mugging in which two men scuffled over a bag.

Participants were then asked to indentify suspects from two different video line-ups. In the first line-up the perpetrator was present, but in the second he was absent. In both scenarios it was made clear that the suspect may or may not be present. How confident participants were that they had identified the suspect in both line-ups was then assessed.

The results showed that older people were more likely to mistakenly identify the suspect in the second line-up, even though he was actually absent.

Dr Kaye said: "It's interesting that older people felt more confident about their selection when they were wrong - to the point where they had imagined someone to be in the line-up who wasn't there. As we age our accuracy as an eye-witness changes which is something police professionals should take into consideration in these circumstances."

Full oral presentation paper title: 'Age effects on confidence and false recognition in eye-witness identification.'