On Wednesday, the Supreme Court heard arguments in United States v. Windsor on the Defense of Marriage Act (DOMA), which stipulates that no state shall be required to respect any other state's law respecting same-sex marriage, and in section three, that marriage is defined by the federal government as between a man and a woman. DOMA does not actually outlaw gay marriage, which is legal in nine states and the District of Columbia, but rather denies gay couples over 1,000 benefits of marriage, such as tax privileges and Social Security benefits.
The case centers on whether section three violates the Equal Protection Clause of the Fourteenth Amendment. (The court may not answer that question if they rule that the Executive Branch has jurisdiction or that the plaintiff doesn't have enough of a proprietary stake in the case.) However, DOMA may be unconstitutional for an entirely different reason: states' rights and the Full Faith and Credit clause. Justice Kennedy, the crucial swing vote, hinted in oral argument that this is his main concern, and he is right to focus on it. DOMA far overextended the power of Congress.
DOMA was originally passed as an preemptive strike against gay marriage advocates using the Full Faith and Credit clause of Article IV, Section 1 of the Constitution, which forces states to recognize laws and judgements of other states. Democratic legislators and the ACLU criticized the law as a novel use of Congress' authority to limit the Full Faith and Credit clause, but its defenders said DOMA takes advantage of language in Article IV that allows Congress to "prescribe the Manner in which such Acts, Records and Proceedings shall be proved, and the Effect thereof."
The most cited law review articles on the subject disagree with this interpretation. Invalidating an act is much more than influencing the "manner" or "effects" of an act. In the words of Scott Rushay-Kidd in the Columbia Law Review, "[DOMA] is premised on the unprecedented, faulty, and potentially far-reaching claim that Congress can abrogate Full Faith and Credit based on a distaste for the laws of particular states. A historical and structural analysis of the Full Faith and Credit clause, as well as basic principles of federalism, suggest that Congress possesses no such power."
Justice Kennedy, in oral argument, grilled the pro-DOMA advocate along these lines. If anything, he did not go far enough. "Full Faith and Credit" was mentioned twice, but only in passing by the pro-DOMA advocate! Instead, Justice Kennedy objected that DOMA overextended the power of the federal government over marriage, saying "...it has 1,100 laws, which in our society means that the Federal Government is intertwined with the citizens' day-to-day life, you are at real risk of running in conflict with what has always been thought to be the essence of the State police power, which is to regulate marriage, divorce, custody." I applaud Justice Kennedy for couching his argument in the language of federalism, and not just Equal Rights, but explicitly noting that DOMA endangers the Full Faith and Credit clause is just as important.
The Supreme Court is generally path-dependent. Once a lower court has interpreted a case according to one statue or clause, or the Supreme Court has done the same, it is loath to bring in a new mechanism of interpretation, given how far-reaching the effect of its decisions are. Despite the Court's reluctance to expand a new avenue of interpretation, it is crucial for the court to strike down DOMA based on the Full Faith and Credit Clause given that the original act was an unlawful expansion of Congress' power. Using the Full Faith and Credit Clause does not preclude the Court from also citing the Equal Protection clause. It would establish discrimination based on sexual orientation as deserving of strict scrutiny (the court's highest standard for laws), just as gender is, while also stripping Congress of its ability to pass laws structured like DOMA in the future.
It's not too often that social progressives and states' rights activists can find an issue to come together on, but DOMA should be a point of unison for the two groups, given that it represents both discrimination and impingement on states' rights by the federal government. Repealing DOMA won't mean all states have to marry gay couples, but it will validate their sister states' right to do so. Perhaps more importantly, it will send a clear signal to Congress that they can't arbitrarily interfere with the legislative process at the state level in the future.