Do sober eyewitnesses outperform alcohol intoxicated eyewitnesses in a lineup?

Abstract

Although alcohol intoxicated eyewitnesses are common, there are only a few studies in the area. The aim of the current study is to investigate how different doses of alcohol affect eyewitness lineup identification performance. The participants (N= 123) were randomly assigned to a 3 [Beverage: control (0.0 g/kg ethanol) vs. lower (0.4 g/kg ethanol) vs. higher alcohol dose (0.7 g/kg ethanol)] X 2 (Lineup: target-present vs. target-absent) between-subject design. Participants consumed two glasses of beverage at an even pace for 15 minutes. Five minutes after consumption the participants witnessed a film depicting a staged kidnapping. Seven days later, the participants returned to the laboratory and were asked to identify the culprit in a simultaneous lineup. The result showed that overall, the participants performed better than chance; however, their lineup performance was poor. There were no significant effects of alcohol intoxication with respect to performance, neither in target-present nor target-absent lineups. The study's results suggest that eyewitnesses who have consumed a lower (0.4 g/kg ethanol) or a higher (0.7 g/kg ethanol) dose of alcohol perform at the same level as sober eyewitnesses in a lineup. The results are discussed in relation to the alcohol myopia theory and suggestions for future research are made.