On the Strength of Trust: The Moderating Role of Certainty in Judgments of Authorities

Communication studies often measure trust in or credibility of message sources as if their effects on critical consequences such as behavior are uniform across individuals and contexts. Drawing on the literature of attitude strength, this paper argues that considering the certainty of trust judgments enables researchers to better understand when trust is likely to induce desired behavior such as cooperating with a judged authority. Using two studies in different contexts, one from a local environmental dispute and another from the national-level COVID-19 pandemic in the U.S., the current paper shows that communication practices (e.g., personal interaction, news media use, interpersonal discussion) reinforce people’s certainty in their judgment of authorities. This certainty, in turn, interacts with the effect of trust such that trust judgments greater in certainty are more likely to lead to behavioral intentions.