Here is an excerpt from a study I relied upon in one of my law-adjacent essays on regulating misinformation. I’m not an expert on conspiracy theories, but I enjoyed the breadth and analysis in this one:

“While findings on collective narcissism primarily emphasize how a strong ingroup identity—in the form of feelings of ingroup superiority—predicts belief in conspiracy theories, other individual difference traits are more directly linked with a structural tendency to perceive outgroups as threatening. Two key individual difference variables commonly connected to stereotyping and intergroup conflict are authoritarianism and social dominance orientation. Several studies have found positive relationships between belief in specific conspiracy theories and these two individual difference variables (Abalakina‐Paap et al., 1999; Imhoff & Bruder, 2014; Swami, 2012). In sum, people who are dispositionally likely to perceive their ingroup as superior or to perceive outgroups as threatening display increased belief in conspiracy theories.

Furthermore, experimental studies support the idea that the two key ingredients of intergroup conflict—a strong ingroup identity and a sense of outgroup threat—jointly stimulate belief in conspiracy theories. For instance, taking the perspective of members of a group increases belief in conspiracy theories, but only after receiving information that the group is under threat (Van Prooijen & Van Dijk, 2014). Likewise, self‐uncertainty predicts increased conspiracy beliefs, but only among people who feel included in a group (Van Prooijen, 2016). These studies suggest that a strong ingroup identity increases conspiracy theories, but only in conjunction with a sense of threat. Experimental studies conducted in Indonesia yielded similar conclusions. People whose Muslim identity was made salient believed conspiracy theories—blaming terrorist attacks in Indonesia on a Western conspiracy—more strongly than people whose Muslim identity was not made salient, but only when the West was described as threatening to Muslims (Mashuri & Zaduqisti, 2015). Finally, basic sense‐making processes predict conspiracy theories only when a hostile outgroup is salient (Marchlewska, Cichocka, & Kossowska, 2018).”

Jan‐Willem van Prooijen and Karen M. Douglas, Belief in conspiracy theories: Basic principles of an emerging research domain, European Journal of Social Psychology (2018).