In a characteristically thoughtful and original essay, Professor Mark Tushnet contends that Roper v. Simmons is consistent with a long line of U.S. Supreme Court precedent utilizing international sources in constitutional interpretation. Given this consistency with prior practice, Professor Tushnet asserts that the controversy over Roper “must rest on something new in constitutional discourse.” He finds the “something new” in two sources: the rise of originalism and renewed “concern for the place of the United States in the modern international order.”

In this brief response, I suggest two more sources for the controversy over Roper. The first is an additional “something new in constitutional discourse”: the emerging transnational judicial dialogue among the world's constitutional courts on human rights issues and the concomitant emergence of constitutional courts as important mediators between domestic and international law. Building on Professor Tushnet's insights with respect to Roper's impact on debates over national identity, I ground criticism of the Court's decision in part on the fear that American judges might become active participants in the dialogue on human rights and that this might have negative consequences for the United States' so-called national identity.

Second, I argue that controversy over Roper is grounded in part on “something new” with respect to the Court's use of non-U.S. sources. Seen against the backdrop of the emerging transnational judicial dialogue on human rights, Justice Anthony Kennedy's reliance on nonbinding human rights treaties represented a significant departure from – or at least expansion of – the Court's prior practice.