Everyone knows it's a hoax: The role of perceived descriptive norms in conspiracy beliefs

People's belief in conspiracy theories is shaped by social influence processes. This contribution investigated these processes in six studies (total N = 2906) by examining the role of descriptive norms, that is, the perception that others endorse conspiracy theories. Studies 1a and 1b indicate that stronger own conspiracy beliefs are associated with overestimating conspiracy beliefs in others. Studies 2a and 2b showed that experimentally exposing participants to a conspiracy theory increased their perceptions of the extent others believed this conspiracy theory. Studies 3 and 4 manipulated descriptive norm information. Although abstract, context-free normative information did not influence conspiracy beliefs (Study 3), providing factual statistical information showing that most people do not believe in various specific conspiracy theories reduced participants’ own conspiracy beliefs (Study 4). These results indicate that perceived descriptive norms are important to understand why people often believe the conspiracy theories spread by others.