This article presents and tests an original theory that truth commissions (TCs) inspire democratic behaviors, but have little discernible impact on democratic institutions. Using quantitative analyses of countries undergoing transitions between 1970 and 2015, and accounting for endogeneity of TCs, we find that these temporary bodies are associated with greater democratic participation and state agent observance of physical integrity rights. However, they have no measurable effect on institutions like fair elections, rules regulating political association, liberal checks on the executive, or judicial independence. This contradicts a key argument in the transitional justice literature that TCs catalyze institutional reform through investigation and extensive recommendations. This article’s findings might encourage those who intend to use these bodies as a tool to promote citizen activism or police restraint. However, the findings might discourage those who hope TCs could jump-start judicial reforms or create a firewall against executive overreach.