A review of the theory and research concerning factors affecting persuasion suggested the hypothesis that eyewitness confidence is an important factor in jurors' perceptions of the witness' credibility. Three experiments were conducted using mock jurors to test this hypothesis. Experiment I found that perceptions of credibility varied as a function of witness confidence. Experiment 2 found that perceptions of the accuracy of the witness' description and identification of the suspect varied as a function of her expertise, whereas perceptions of the accuracy of her account of the crime varied as a function of her confidence. Perceived expertise also varied as a function of witness confidence. Because Experiments 1 and 2 used college students as subjects, Experiment 3 was conducted to replicate these findings in an older subject sample. Theoretical and practical implications of the findings are discussed.