This week, the Supreme Court will hear argument in a case challenging section 3 of the Defense of Marriage Act (DOMA), which creates a federal definition of marriage, as well as an appeal of the Proposition 8 case out of California. Conservatives generally agree on Prop 8, since the Ninth Circuit's opinion, like that of the district court, represents a shabby attempt to impose gay marriage by judicial fiat, a la Roe. Clearly, SCOTUS should reverse on Prop 8.
But conservatives are split on DOMA. Many have jumped on the anti-DOMA bandwagon on the basis of federalism; i.e., that the federal government has no power to define marriage. This position was advanced in a brief by scholars with impeccable credentials (e.g., Randy Barnett, Jonathan Adler, etc).
With respect, I think the anti-DOMA argument is misguided. First, let's remember that DOMA does not change any state's definition of marriage. It says that, for purposes of federal law, any reference to "marriage" is limited to the marriage of one man and one woman. The federalism argument goes like this: marriage is a creature of state law. Congress has no enumerated power to interfere with state regulation of marriage.
But wait: roads and bridges are creatures of state law. So are schools. Congress has absolutely no enumerated power to meddle with those, either. And yet, federal law is chock full of mandates and coercive funding conditions that don't merely interfere with state control, but entirely usurp state control. Corporations, also, are creatures of state law. But that didn't stop Congress from passing Sarbanes-Oxley and other laws that micromanage corporate governance.
I would like to see all these laws struck down, but DOMA is a different issue. DOMA simply says: to the extent the federal government has any business referring to "marriage" in a statute, the federal government can define that term. DOMA affects approximately 1,100 federal laws. I daresay many of those laws are unconstitutional as beyond Congress's enumerated powers. But that would be the case whether or not Congress defined "marriage" in those statutes.
If Congress passed a law saying, for example, that states must adopt a particular definition of marriage in order to keep HHS funding (or education funding, etc), I would object to such a law, as I object to all conditional funding statutes. But that is not the case here. States that adopt gay marriage are not penalized by DOMA (indeed 9 states have adopted SSM since DOMA's passage).
I should note that I used to buy the federalism argument, but the more I studied it -- and searched the scholars' brief for pearls of wisdom -- the less persuaded I became. I have also found Ed Whelan's pieces at NR's Bench Memos blog to be very useful in blunting the federalism attack. There is a strong argument to be made for striking d0wn federal statutes that exceed Congress's power. But I fail to see the problem with a statute that simply amends existing federal laws by adding a definition.