The effects of alcohol and co-witness information on memory reports: a field study

Witnesses who discuss a crime together may report details that they did not see themselves but heard about from their co-witness. Co-witness information may have beneficial and harmful effects on memory accuracy depending on whether the information was correct or incorrect.

Given the prevalence of intoxicated witnesses, it is imperative to understand how alcohol influences this effect.

The present study asked pubgoers (n = 67) at varying levels of intoxication to recall a mock crime video after having also watched a video witness statement containing both correct and false information.

Increased intoxication was associated with decreased confidence, completeness and accuracy, but no increased tendency to report false information. Exposure to incorrect post-event information (PEI) can lead to the incorporation of incorrect information, whereas exposure to correct PEI increased accuracy, regardless of individuals' alcohol intoxication status.

Thus, whilst discussion and intoxication can negatively impact eyewitness memory, discussion may also have benefits for both sober and intoxicated witnesses.