Research finds intoxicated witnesses can give more details to police a week after an incident

Research into the memory recall of heavy drinkers who witness harrowing incidents has revealed insights for police investigative approaches to complex and emotionally charged cases.

The study from Abertay University in collaboration with Glasgow Caledonian University and the University of Glasgow found that carrying out a second, delayed police interview with people who had witnessed an incident may yield more information than relying solely on details given directly by a drunk witness or victim at a scene.

Published in the journal Frontiers in Psychology, the project involved 60 participants who were all assessed as heavy drinkers.

Study participants consented to watch a video of a serious car accident and half consumed alcohol after the event while the other half received a placebo drink.

Across two interview sessions—one conducted immediately and then another one-week afterwards—participants were asked to recall what they could remember about the accident.

While the alcohol and placebo groups remembered similar amounts of details, the alcohol group recalled more details and were also more certain about their responses when interviewed again after one week.

The findings have implications for the criminal justice system, showing that witnesses and victims who drink after seeing an incident may benefit from a second interview with officers, which could add further details to the police investigation.

Dr. Julie Gawrylowicz of Abertay University's Division of Psychology and Forensic Sciences worked on the project with Benjamin Butterworth and Dr. Karen Lorimer of Glasgow Caledonian University and Dr. Christopher Hand of University of Glasgow.

Dr. Gawrylowicz said, "Given that a high number of crimes take place at or near places where alcohol is consumed, it is vital to study how to best support victims and witnesses who were drunk before, during, or after they witnessed a crime to ensure they can provide best evidence during police interviews. The prospect of potentially traumatic memories being experienced and processed in the days following an incident is also an area of concern in terms of the mental health of victims or witnesses, particularly amongst heavy drinkers where chaotic lifestyles may also be a factor."