Given the potential political and social significance of conspiracy beliefs, a substantial and growing body of work examines the individual-level correlates of belief in conspiracy theories and general conspiratorial predispositions. However, although we know much about the psychological antecedents of conspiracy endorsement, we know less about the individual-level political causes of these prevalent and consequential beliefs. Our work draws from the extant literature to posit that endorsement of conspiracy theories is a motivated process that serves both ideological and psychological needs. In doing so, we develop a theory that identifies a particular type of person—one who is both highly knowledgeable about politics and lacking in trust—who is most susceptible to ideologically motivated conspiracy endorsement. Further, we demonstrate that the moderators of belief in conspiracy theories are strikingly different for conservatives and liberals.