Beliefs versus reality: People overestimate the actual dishonesty of others

Do people believe that others are similarly, more, or less dishonest than they truly are? The accuracy of dishonesty beliefs is not only important for psychological knowledge, but also has implications for organizations and policymaking. In this paper, Study 1 presents a research program on moral decision-making comprising 31 different effects from 11 experiments, where participants could anonymously lie for personal gain. Crucially, participants were also asked to estimate what percentage of other people would lie in the same situation. An internal meta-analysis summarizing all belief-behavior comparisons revealed that people substantially overestimate others' dishonest behavior ( g = 0.61; k = 31; N = 8126), by 13.6 percentage points on average. This effect holds across study contexts and participants' own behavior, and 63.5% of participants overestimated dishonesty by 5 percentage points or more (only 25.4% underestimated it). We then examined potential consequences of biased dishonesty beliefs in three pre-registered follow-up studies. Study 2 ( N = 981) found that providing correct information about actual honesty levels enhanced general prosocial expectations (e.g., trustworthiness, fairness). Study 3 ( N = 285) revealed that professional managers have pessimistic beliefs also about people's real-world dishonesty (e.g., insurance fraud, workplace theft), and moral pessimism predicted greater support for freedom-restrictive countermeasures to reduce dishonesty (e.g., surveillance). Study 4 ( N = 741) demonstrated that providing managers with correct information about actual honesty levels causally reduced their support for freedom-restrictive countermeasures. In conclusion, the pessimistic bias in dishonesty beliefs about others is robust, and it shapes prosocial expectations and policy preferences.