parties of the same sex." Ala. Code §30–1–19(e) (2011). When the couple files their next federal tax return, may it be a joint one? Which State's law controls, for federal-law purposes: their State of celebration (which recognizes the marriage) or their State of domicile (which does not)? (Does the answer depend on whether they were just visiting in Albany?) Are these questions to be answered as a matter of federal common law, or perhaps by borrowing a State's choice-of-law rules? If so, which State's? And what about States where the status of an out-of-state same-sex marriage is an unsettled question under local law? See Godfrey v. Spano, 13 N.Y.3d 358, 920 N.E.2d 328 (2009). DOMA avoided all of this uncertainty by specifying which marriages would be recognized for federal purposes. That is a classic purpose for a definitional provision.
Further, DOMA preserves the intended effects of prior legislation against then-unforeseen changes in circumstance. When Congress provided (for example) that a special estate-tax exemption would exist for spouses, this exemption reached only opposite-sex spouses—those being the only sort that were recognized in any State at the time of DOMA's passage. When it became clear that changes in state law might one day alter that balance, DOMA's definitional section was enacted to ensure that state-level experimentation did not automatically alter the basic operation of federal law, unless and until Congress made the further judgment to do so on its own. That is not animus—just stabilizing prudence. Congress has hardly demonstrated itself unwilling to make such further, revising judgments upon due deliberation. See, e.g., Don’t Ask, Don’t Tell Repeal Act of 2010, 124 Stat. 3515. The Court mentions none of this. Instead, it accuses the Congress that enacted this law and the President who signed it of something much worse than, for example, having acted in excess of enumerated federal powers—or
