This paper analyzes constitutional dialogue by comparing a constitutional system that (almost) entrenches judicial supremacy - the United States - with a constitutional system that seeks to reconcile a judicial and legislative role in constitutional interpretation - Canada. The argument has three parts. The second part critically examines the scholarship on constitutional dialogue in Canada and the United States. Dialogue theory in the United States focuses on how societal actors respond to judicial decisions whereas Canadian dialogue theorists emphasize legislative sequels to judicial review. The question is why did dialogue take a different path in Canada than in the United States. The third part analyzes this question. The American Supreme Court enjoys a greater degree of autonomy in interpreting the constitution than does the Canadian Supreme Court. Constitutional politics, not constitutional text, however, decisively shaped the tools available to political actors to respond to judicial decisions both in Canada and in the United States. The fourth part argues that weakening judicial supremacy, as has occurred in Canada, has a democratic pay-off. Constitutional systems that empower legislatures to share in the task of judicial review are more likely to engender trust between competing political factions; judicial supremacy, on the other hand, is more likely to facilitate political polarization.