The purpose of this study was to examine an extra-legal variable that may affect the credibility of a defendant and the alibi corroborator's testimonies. In this study, the facial appearance of the alibi corroborator was manipulated to resemble the defendant or the trial judge to different degrees using facial morphing software. Participants serving as mock jurors provided verdicts for a trial summary and rated the credibility of an alibi corroborator. It was hypothesized that as the facial resemblance shared between an alibi corroborator and a defendant increased, the less credible the alibi corroborator's testimony would be perceived, resulting in an increase of conviction rates for the defendant. On the other hand, when the alibi corroborator resembled the judge, it was hypothesized that the credibility of the alibi corroborator would increase and this would result in fewer convictions. The results revealed that when the facial resemblance was 66%, the defendant was significantly more likely to be convicted, χ 2 (1) = 5.00, p = 0.03, Φ = 0.18, if the alibi corroborator looked like the judge ( M = 0.55) than if he looked like the defendant, ( M = 0.37). Implications for juror decision-making and future research are discussed.
