In the 1900 Supreme Court case The Paquette Habana, the Supreme Court declared “International law is part of our law, and must be ascertained and administered by the courts of justice of appropriate jurisdiction as often as questions of right depending upon it are duly presented for their determination,” building on more than a century of practice. In the years that followed, international law became more formalized, with the creation of the Permanent Court of International Justice, which eventually became the International Court of Justice. These international courts were granted exclusive jurisdiction over disputes between states, with their consent, as well as the authoritative interpretation of treaties, if the treaties so provided. But what happens when the views of a US court and an international court conflict? Which view prevails? This question came to a head in Medellín v. Texas, a 2008 death penalty case involving the proper interpretation of the Vienna Convention on Consular Relations. Join the Constitutional Law Center to hear Alan Mygatt-Tauber discuss these issues based on his new book, Medellín v. Texas: International Law, Federalism, and the Execution of Jose Medellín.