by Angela Gregory

Recent legal research indicates that incorrect identification is a major factor in many miscarriages of justice.

It also suggests that identification of people by witnesses in a courtroom is not as reliable as commonly believed. Recent studies do not support the degree of faith judges, jurors, lawyers and the police have in eyewitness evidence.

The law Commission recently published an educational paper, “Total Recall? The Reliability of Witness Testimony”, as a companion guide to a proposed code of evidence. The paper finds that commonly held perceptions about how our minds work and how well we remember are often wrong. But while human memory is fragile and subject to change, it should not be underestimated.

In court witnesses are asked to give evidence about events, and judges and juries assess its reliability. The paper points out that memory is complex, and the reliability of any person's recall must be assessed individually.

Both common sense and research say memory declines over time. The accuracy of recall and recognition are at their best immediately after encoding the information, declining at first rapidly, then gradually. The longer the delay, the more likely it is that information obtained after the event will interfere with the original memory, which reduces accuracy.

The paper says subsequent interviews or media reports can create such distortions. "People are particularly susceptible to having their memories modified when the passage of time allows the original memory to fade, and will be most susceptible if they repeat the misinformation as fact.”

Witnesses may see or read information after the event, then integrate it to produce something other than what was experienced, significantly reducing the reliability of their memory of an event or offender, " Further, witnesses may strongly believe in their memories, even though aspects of those memories are verifiably false.”

Leading questions can lead to mistakes. If witnesses are asked whether the offender had a beard, they may incorporate an imaginary beard into their memories. Subsequent questioning can reinforce the error through repetition.

Research also shows the accuracy of witnesses descriptions of suspects can vary greatly. In one study the person's gender was reported perfectly by 100 percent of witnesses, hair colour about 73 per cent accurately, but facial hair or speech was reported incorrectly in two-thirds of reported descriptions.

A 1990 study gives strong support for the hypothesis that even a mild level of intoxication can significantly impair memory, but the paper notes that there have been only limited studies. Where a case against a defendant depends on identification evidence, the judge must continue the practice of warning the jury to be cautious.

The paper says it is generally agreed that the memories of adults and children are fallible. Nevertheless, even preschoolers can form reliable memories. Young children depend on context to promote memory, and spontaneously reportless. Children may recall more information with adequate support, but the type of support and questioning is critical. Methods of drawing out information have to be carefully monitored.

Although research shows the accuracy of both adults and children can be affected by leading or suggestive questions, the ability to resist the influence of external suggestion increases with age.

Children may change their account of an event, not because their memory has altered but because they with to comply with the suggestion of an adult in authority, or because they interpret repeated questioning as an indication their first response is judged wrong.

An area of research still relatively unexplored is whether young children have difficulties distinguishing between real and imagined events. The paper concludes that while children are often seen as unreliable witnesses, research does not bear that out. The code provides alternative ways for children to give evidence to increase accuracy, and gives judges guidance on what to tell a jury to help assess the evidence of very young children.

It is generally agreed some adults who experience sexual abuse may recall memories of the abuse after forgetting it. There is no research to indicate recalled memories are more or less accurate than memories available all along.

The paper says it is impossible to distinguish a true from a false memory and it is dangerous to use confidence, vividness and detail as indicating truth.

False memories can be induced under hypnosis, and experiments have indicated it is possible, although difficult, to implant false memories of entire events by suggestion.

The paper says further research is required into interview techniques and conditions under which false memories and reports of abuse are most likely to arise.

It seems that deciding whether any memory is to be finally assessed as reliable or the treacherous ally of invention will largely remain a challenge for judges and juries.