Tuesday the Supreme Court slipped the Gordian knot of a case that could have come straight from a law school exam, involving federalism, treaty interpretation, the scope of executive power, criminal procedure, and conflicts between international and domestic law. The issues in Medellin v. Texas boiled down to: 1) Whether a particular decision of the International Court of Justice is automatically binding on Texas courts and, if not, 2) Whether President Bush made it binding by issuing a memorandum to then-Attorney General Alberto Gonzales. The Court answered in the negative on both counts by a 6–3 margin.

The result of this decision is that neither the ICJ (the so-called “World Court”) nor the president acting alone can force states to review criminal cases involving foreign nationals. The underlying treaty at issue – which gives foreign nationals accused of a crime the right to meet with consular officials – is not enforceable in the absence of implementing legislation from Congress. The ICJ ruling is similarly not self-executing, and does not gain legal effect merely because the president tells the states to abide by it.

The Supreme Court has thus protected America’s carefully calibrated system of federalism and checks and balances by preventing an international court from overriding a state’s duly enacted (and constitutionally sound) law. Just as importantly, the Court correctly rejected the argument that the president has the power to enforce against the states a treaty that is, in the absence of congressional action, enforceable only by diplomatic means. Telling state courts how to do their jobs is simply not among the powers of the nation’s chief executive.