UPDATED 1:49 p.m.

The Supreme Court, in a sweeping rejection of claims of power in the presidency, ruled 6-3 on Tuesday that the President does not have the authority to order states to relax their criminal procedures to obey a ruling of the World Court. The decision came in the case of Medellin v. Texas (06-984). Neither a World Court decision requiring U.S. states to provide new review of criminal cases involving foreign nationals, nor a memo by President Bush seeking to enforce the World Court ruling, preempts state law restrictions on challenges to convictions, the Court said in a ruling written by Chief Justice John G. Roberts, Jr.

The Court explicitly, and with emphasis, rejected a presidential argument that the nation’s Chief Executive has power, on his own, to make an international treaty into binding law inside the U.S. That can only be done by Congress, it stressed.

The decision, aside from its rebuff of presidential power, also treats the World Court ruling itself as not binding on U.S. states, when it contradicts those states’ criminal procedure rules. The international treaty at issue in this dispute — the Vienna Convention that gives foreign nationals accused of crime a right to meet with diplomats from their home country — is not enforceable as a matter of U.S. law, the Roberts opinion said. And the World Court ruling seeking to implement that treaty inside the U.S. is also not binding, and does not gain added legal effect merely because the President sought to tell the states to abide by the decision, the Court added.

The ruling also is a defeat for 51 Mexican nationals who won a World Court decision in 2004, finding that U.S. states had denied them their consular access rights and advising the U.S. government to take steps to enforce the ruling. None of the 51 had been given access to a consular officer while their cases proceeded. In the specific case, Mexican national Jose Ernesto Medellin, convicted in state courts of murder, had sought to rely on the Vienna Convention. Texas courts ruled that he had defaulted on that right by failing to raise the issue at his trial. He then pursued a habeas challenge, arguing that the World Court decision and the Bush memo overrode the state default rule.

The Bush Administration did not agree with the World Court ruling, and, in fact, withdrew from the international protocol that gave the World Court the authority to enforce the Vienna Convention against countries that had signed it. Even so, Bush issued a memo in February 2005 agreeing that the U.S. would seek to obey the World Court, and he told the states involved to “give effect” to that tribunal’s decision in the cases of the 51 Mexicans involved in the World Court case. The U.S. government stepped into the case in Texas courts to assert the authority of the President to lay upon the states a duty follow his mandate to obey the World Court. The case thus reached the Supreme Court as a major test of presidential authority, in seeking to enforce treaty obligations, to override contradictory state criminal procedure rules. In that test, the presidency clearly lost.

The Chief Justice’s opinion was supported in full by Justices Samuel A. Alito, Jr., Anthony M. Kennedy, Antonin Scalia and Clarence Thomas. Justice John Paul Stevens supported the result only. Stevens said that he found the issue to be a closer one than the Roberts opinion allowed, but said that he was persuaded “in the end” that the treaty did not authorize the Supreme Court to enforce the World Court’s ruling.

Justice Stephen G. Breyer dissented, joined by Justices Ruth Bader Ginsburg and David H. Souter.

In rejecting the Mexican nationals’ reliance on the World Court’s decision, the Chief Justice wrote that the ruling did impose “an international obligation on the part of the United States.” But that did not automatically give it legal effect “such that the judgment of its own force applies in state and federal courts.” The Court said that the legal effect of a World Court decision is controlled by Article 94 of the United Nations Charter, which means, the Court went on, that the U.S. and other member countries that submitted to World Court jurisdiction on a given dispute assume “a commitment…to take further action through their political branches to comply.” Thus, it added, Article 94 “is not a directive to domestic courts. It does not provide that the United States ‘shall’ or ‘must’ comply” with such a ruling. Enforcement depends, it said, upon a diplomatic, not a judicial, remedy — that is, a political, not a legal, enforcement mechanism. The Court went on to say that this mechanism should not be turned over to state and federal courts in place of the political branches of the government.

“Our Framers established a careful set of procedures that must be followed before federal law can be created under the Constitution — vesting that decision in the political branches, subject to checks and balances,” Roberts wrote. To turn over to the judiciary the task of deciding when a treaty becomes domestic law, the Chief Justice added, would be to give the courts “the power not only to interpret but also to create the law.”

Turning to the question of the President’s authority to make the World Court decision binding domestically, the Court said that the Chief Executive’s power to act, as with the exercise of any governmental power, must stem either from an act of Congress or from the Constitution itself.” It found no such authorization, rejecting claims that the Vienna Convention itself gives the President authority to implement the World Court ruling finding a U.S. violation, that Congress has acquiesced in that authority, that the President on his own has power to resolve international disputes apart from treaty enforcement, and that presidential power of that kind at issue is given by the Constitution’s allocation of power in the President to make sure that laws are “faithfully executed.”

Having found that the Vienna Convention is the kind of treaty that can only be executed in the U.S. if Congress expressly agrees to that, the Court said that the President may not do that on his own, or under some his interpretation of a treaty like the Vienna Convention. There is no congressional legislation to turn that Convention into domestic law, the Court found. If the President were to seek to unilaterally create domestic law, when a treaty ratified by the Senate was not a self-executing pact, that would contradict the Senate’s action of ratifying the treaty with the understanding it was not being made into domestic law. In that situation, the President’s power would be “at its lowest ebb,” quoting the famous formula laid out by Justice Robert Jackson in the Steel Seizure case in 1952 (Youngstown Sheet & Tube v. Sawyer).

Quoting Founding Parent James Madison, saying that the President “in whom the whole executive power resides cannot of himself make a law,” the Chief Justice commented that that would “seem an apt description” of President Bush’s claim that he could unilaterally turn the Vienna Convention into domestic law.

Examining the government claim that Congress had, in fact, acquiesced in turning the World Court decision into domestic law, the Chief Justice found that none of the instances cited “remotely involved transforming an international obligation into domestic law and thereby displacing state law.”

The opinion stressed that the President could opt to comply with a treaty’s obligation “by some other means, so long as they are consistent with the Constitution.”

Refuting the government claim that the President’s February 2005 memorandum was a sufficient basis for implementing domestically the World Court ruling, the Chief Justice wrote: “The government has not identified a single instance in which the President has attempted (or Congress has acquiesced in) a Presidential directive issued to state cours, much less one that reaches deep into he heart of the State’s police powers and compels state courts to reopen final criminal judgments and set aside neutrally applicable state laws.”