Here’s a new topic for Chairman Sensenbrenner’s suddenly awake Judiciary Committee: “RECKLESS JUSTICE: Does the Marriage Protection Amendment Trample the Constitution?” Of course, the case seems open and shut. In the landmark Lopez case a decade ago, Chief Justice Rehnquist opened with the basics: “We start with first principles. The Constitution establishes a government of enumerated powers.”

Marriage law has always been reserved to the states in our federal system. Law professor Dale Carpenter calls the Marriage Protection Amendment, which the Senate will debate and vote on next week, “a radical intrusion on the nation’s founding commitment to federalism in an area traditionally reserved for state regulation” in his Cato study released today.

Conservatives claim to believe in federalism, until the states do things they don’t like. Then they turn into New Deal liberals, believing that the federal government should correct the errors of the 50 states. The proposed Marriage Protection Amendment would not just protect states from being forced to recognize same-sex marriages made in other states, as some proponents claim. It would forbid any of the several states from deciding — through court decision, legislative action, or even popular initiative — to extend marriage to gay couples. Depending on the interpretation of its language, it may even ban civil unions and domestic partnerships.

Of course, it’s not good lawmaking to propose an amendment to the Constitution whose language is so unclear, even to its supporters. But then, this really isn’t lawmaking. Majority Leader Bill Frist knows the amendment won’t pass the Senate next week. It failed in 2004 and is likely to get only a handful more votes this time. A majority leader usually doesn’t bring legislation to the floor that he knows will fail. Frist must have some other purpose in mind in bring this amendment up for a futile vote.