People update their injunctive norm beliefs and moral judgements after receiving descriptive norm information

How do descriptive norms shape injunctive norm beliefs and what does this tell us about the cognitive processes underlying social norm cognition? Across six studies (N=2,671), we examined whether people update their injunctive norm beliefs—as well as their moral judgements and behavioral intentions—after receiving descriptive norm information about how common (or uncommon) a behavior is. Specifically, we manipulated the descriptive normativity of behaviors, describing behaviors as uncommon (20% of people were doing the behavior) or common (80% of people were doing the behavior), and the type of behavior across studies (fairness, conventional, harm, preference). To measure belief updating, we assessed beliefs prior to and after receiving information about the descriptive norm. We had three main findings: first, participants positively updated their prior injunctive norm beliefs, moral judgements, and behavioral intentions (i.e., rated behaviors more injunctively normative and moral) after receiving a common descriptive norm and negatively updated their beliefs (i.e., rated behaviors less injunctive and moral) after receiving an uncommon descriptive norm, and updated to a larger extent for the common than uncommon descriptive norm. Second, participants were more likely to update their beliefs about what is moral for others compared to what is moral for the self. Third, participants updated their beliefs to a greater extent for fairness and conventional behaviors compared to harm behaviors and preferences. Together, our findings suggest that descriptive norms shape our injunctive norm beliefs and moral judgements and help to paint a fuller picture of the social cognition of social norms.