California Signs Global Warming Pact with U.K.

After leaving the White House this week during his consultations with President Bush, UK Prime Minister Tony Blair met with California’s Governor Arnold Schwarzenegger to announce an agreement to start a global-warming-reducing emissions-trading market.

Wait a minute, even though California often seems like a foreign country to many of us in the States, can California actually sign an agreement with a foreign country? And does such an agreement have any status under international law?

The answer is a little murky, as a forthcoming article I am publishing with the Yale Law Journal suggests. Governors are actually doing more and more of this sort of international agreement-making all the time, and it is usually OK as long as the agreement is not government-to-government but agency-to-agency. Still, there are possible constitutional violations here, because the Constitution, article I, section 10 plainly prohibits states from making international agreements with foreign countries absent congressional approval. But the question has never been definitively resolved by a court.