The Persuasive Effects of Source Credibility in Buy and Lease Situations

Communication strategists frequently use highly credible individuals as spokespersons for their advocacy. Lawyers recruit expert and trustworthy witnesses to support their clients' positions. Politicians seek highly regarded individuals and groups to endorse their programs and candidacies. Advertisers hire people of high integrity to sponsor their products and services. These strategies are predicated on the belief that highly credible sources are more persuasive than those of lower credibility. Extant research provides qualified support for the belief that highly credible sources enhance persuasion, indicating that this effect is obtained only under certain conditions. Stemthal, Dholakia, and Leavitt (1978) categorized subjects on the basis of their favorability toward the position advocated in a communication. Subjects then were presented a persuasive message attributed to either a highly credible or moderately credible source. The highly credible communicator was found to be more persuasive than the moderately credible source among subjects opposed to the advocacy. In contrast, the less credible source was more influential for subjects favor-