'Memory-freezing' tool to help fight crime

SCIENTISTS at a Scottish university have developed a powerful new crimefighting tool that "freezes" the memory of crime scenes in the minds of potential witnesses, it was revealed yesterday.

The research team, led by scientists at Dundee's Abertay University and Portsmouth University, has used the latest cognitive psychology techniques to enable eye witnesses to record their memories before any potentially crucial information is forgotten.

The system uses a self-administered interview (SAI) form which allows witnesses to capture images and details of crime scenes and perpetrators in their minds - particularly small and seemingly insignificant details that could turn out to be crucial in solving cases.

Tests have shown that witnesses using the form were 42 per cent more accurate than other witnesses who were simply asked to report as much as they could remember.

And it is hoped that the new technique will enable detectives to gather vital information from members of the public who are not originally regarded as crucial witnesses and who might only be interviewed in detail, days after a crime has been committed.

The new "report and recall tool" has been developed by Dr Fiona Gabbert, a psychologist at Abertay University, and her colleague Dr Lorraine Hope from Portsmouth, with the aid of funding from the British Academy.

Dr Gabbert said the details of eyewitness evidence decreased over time. And the longer the gap between witnessing an event and fully recalling it under formal interview conditions, the less accurate and less complete a witness report was likely to be.

She continued: "Decades of research in cognitive psychology demonstrate that memory decay, or forgetting, occurs rapidly at first. In a witnessing situation, this forgetting will occur naturally and within hours of the incident."

At a normal crime scene where there are a number of witnesses, only those whom the police regard as key witnesses are normally interviewed straight. Other witnesses may not be interviewed for days or even weeks.

But the new form, developed by the team, effectively enables witnesses to interview themselves and to record detail immediately after an event.

Dr Gabbert said: "The forensic implications of these findings for current police practice are considerable.

"Research has proven that recalling an event before any substantial forgetting or memory loss has taken place means that the way the event is represented in memory is strengthened, making it easier to recall in future.

"In this way, an early recall attempt serves to protect or 'freeze' the memory against the course of natural forgetting."

Her colleague, Dr Hope, added: "The SAI is not an alternative to a subsequent full police interview. It is a tool to protect witness memory at the earliest possible juncture."

The researchers are now planning a field study involving actual crime scenes.

Putting crime witnesses in the picture

THE "memory freeze" tool is based on the cognitive interview technique, which is aimed at getting witnesses to put themselves "back in the moment" of a crime.

The self-administered interview form asks witnesses to picture in their mind where they were and what they were thinking and feeling at the time they saw a particular event and then to record the details.

Witnesses are encouraged to draw a sketch and not to leave out any information they regard as trivial.

The form also includes prompts to help witnesses describe a perpetrator, including ethnic appearance, complexion, clothing and accent.

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