A Cross-Cultural Test of Competing Hypotheses About System Justification Using Data From 42 Nations

System Justification Theory (SJT) is a thriving field of research, wherein the primary questions revolve around why individuals and groups are motivated to see the systems they depend on as just, fair, and legitimate. This article seeks to answer how accurate the postulates of SJT are when compared to competing self-interest claims of Social Identity and Social Dominance Theory. We addressed the ongoing debates among proponents of each theory by identifying who, when, and why individuals decide to system-justify. We used data comprised of 24,009 participants nested within 42 countries. Multilevel models largely supported the competing claims of Social Dominance and Social Identity Theories over SJT. The most robust findings were: (1) greater objective SES was associated with greater system justification; (2) the consistent positive relationship between subjective SES and system justification was partially mediated by life satisfaction; and (3) both ends of the political spectrum were willing to system-justify more when the political party they favored was in power. The results presented are used to discuss both the current state and future directions for system justification research.