International control over US affairs at even the state level?

Medellin's right to seek legal advice from Mexican diplomats is protected by the 1963 Vienna Convention, an international treaty that President Bush must follow under the U.S. Constitution, said Susan Gzesh, director of the human rights program at the University of Chicago.

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A Father's Plea "If the U.S. is going to disobey the obligations we've undertaken under the Vienna Convention, then other countries could retaliate," Gzesh said. "Bush is following the treaty."

The Bush administration was pulled into the case when Mexico sued the United States in 2003. The International Court of Justice ruled in Mexico's favor in 2004, ordering the United States to review the case. Bush wrote a presidential memo in 2005 saying that the U.S. would comply and order state courts to review the cases.

Bush later withdrew the United States from the Vienna Convention that gives the international court final say in international disputes. But that withdrawal did not change U.S. obligations to follow the treaty...

"If Texas courts are required to follow international law, they can still go ahead with execution," said Scheidegger.

The Supreme Court is not expected to rule in the case until the Spring.