Justice Kennedy's opinion today in Roper v. Simmons, declaring the juvenile death penalty unconstitutional, draws inspiration from foreign precedents. It rejects the notion that reflecting on such foreign precedents is contrary to self-constitution:
Over time, from one generation to the next, the Constitution has come to earn the high respect and even, as Madison dared to hope, the veneration of the American people. See The Federalist No. 49, p. 314 (C. Rossiter ed. 1961). The document sets forth, and rests upon, innovative principles original to the American experience, such as federalism; a proven balance in political mechanisms through separation of powers; specific guarantees for the accused in criminal cases; and broad provisions to secure individual freedom and preserve human dignity. These doctrines and guarantees are central to the American experience and remain essential to our present-day self-definition and national identity. Not the least of the reasons we honor the Constitution, then, is because we know it to be our own. It does not lessen our fidelity to the Constitution or our pride in its origins to acknowledge that the express affirmation of certain fundamental rights by other nations and peoples simply underscores the centrality of those same rights within our own heritage of freedom.
Considered alongside the Court's embrace of international law in Sosa v. Alvarez-Machain, this marks a strong transnationalist turn in the court's jurisprudence. This would be an intriguing subject of a Foreword to the Harvard Law Review's Supreme Court review issue.