When Thinking More Is Detrimental to Judging the Truth: The Roles of Perceived Source Dishonesty and Scrutiny in Veracity Judgments

The effects of perceived source honesty have been studied extensively in the context of persuasion, but their interaction with veracity (i.e., their role in misinformation) has been neglected. For instance, when the veracity of information and the perceived honesty of its source are incongruent (e.g., true information from dishonest sources or false information from honest sources), this could lead to greater scrutiny of information. An exploratory study (N = 410) tested the effects of the congruence of perceived source honesty and veracity on scrutiny of, and belief in, true and false information. In a 2 (honest vs. dishonest source) by 2 (true vs. false statements) between-subjects online experiment, participants rated the perceived veracity of 30 general knowledge statements before completing an adapted version of a message elaboration scale, among other exploratory measures. Tentative evidence from a moderated mediation analysis suggests that true (but not false) information from sources perceived as dishonest (vs. honest) is scrutinised more, despite the absence of a main effect of source honesty on truth ratings. In other words, the incongruent combination of true information and dishonest sources increases information scrutiny. Higher levels of scrutiny, in turn, have a negative effect on truth ratings, meaning that scrutiny reduces rather than improves the accuracy of truth judgments in this case. Overall, results suggest that people err on the sceptical side in judging truth when sources are perceived as dishonest.