To ascertain whether intoxication at the time of a crime affects a witness’s credibility with mock jurors, 240 jury eligible individuals completed an online questionnaire rating the convincingness, confidence, competence, honesty, believability, consistency, credibility, accuracy, and completeness of one of six witness testimonies. Although sober when interviewed, witnesses were either sober, moderately, or severely intoxicated (BAC under/over .08%) during the crime, with half of jurors being provided with this information. Within each condition, the testimony was either long or short, with the former being more complete. From the credibility ratings, a single principal component analysis factor was extracted. Subsequent analysis of variance analyses indicated that knowledge of the witness’s intoxication and a less complete account led to lower credibility ratings. With no main effect of intoxication, the testimony of an intoxicated witness itself was not perceived as less credible. Findings are discussed in relation to the criminal justice system and future research.
