My paper explores the expansion of human rights law as a feature of domestic constitutional law in a context of democratic decay. It discusses the particular case of “Latin American international law,” which combines a distinctive monist tradition of international law with a strong and recent adoption of constitutional review. The question I seek to address is: what can we learn from a case of enhanced monism that has (nonetheless?) rendered a dramatic democratic erosion? Is there a causal relation or is it just a coincidence? More generally, what does this exploration tell us about the future of constitutional democracy? The paper examines the ways in which the Inter-American Court of Human Rights takes stock of, and interacts with, domestic law. Specifically, it looks at recent articulations of that interaction, such as the notion of “judicial dialogue” and the development of a kind of Latin American common law of rights and constitutionalism.