This Article explores the relationship between the legitimacy of international courts (ICs) and expansive judicial lawmaking. We compare lawmaking by three regional integration courts — the Court of Justice of the European Union (CJEU), the Andean Tribunal of Justice (ATJ), and the ECOWAS Community Court of Justice (ECCJ). These courts have similar jurisdictional grants and access rules, yet each has behaved in a strikingly different way when faced with opportunities to engage in expansive judicial lawmaking. The CJEU is the most activist, but its audacious legal doctrines have been assimilated as part of the court’s legitimate authority. The ATJ and ECOWAS have been more cautious, but there is little to suggest that this caution has enhanced the legitimacy of either court. The ATJ has avoided serious challenges from governments, but its rulings have had little political impact. Conversely, the ECCJ’s circumspection has not shielded it from political opposition to its adjudication of clearly-established human rights. This pattern is at odds with the oft-voiced conventional wisdom that expansive judicial lawmaking undermines judicial legitimacy. Our modest goal in this Article is to problematize that claim and to posit an alternative hypothesis — that ICs spark legitimacy challenges due to the domestic political effects of their decisions, regardless of whether those decisions are expansionist.