The case is Gill v. Office of Personnel Management (D. Mass., decided today). The court reasons that, at least as to various benefits provided by the federal government, the distinction that DOMA draws between opposite-sex married couples and same-sex couples married under the laws of those states that recognize same-sex marriage is irrational, and thus violates the equal protection component of the Due Process Clause. And while the opinion discusses the federal government’s traditional reliance on state definitions of marriage, the underlying reasoning in the opinion is broader than that: As I read the opinion, the reasoning is broad enough to require states to recognize same-sex marriages (or at least civil unions), since under the court’s reasoning an opposite-sex-only marriage rule would be similarly irrational.
The rationale is not that different from that given by those state courts that have struck down opposite-sex-only marriage rules; but those have done so under their state constitutions, so there was no chance of review by the U.S. Supreme Court. (Each state supreme court is the ultimate interpreter of the state’s constitution, and the U.S. Supreme Court won’t disturb such an interpretation unless it violates some person or entity’s federally secured rights.) Here, the federal government would presumably appeal to the First Circuit, or face a great deal of public criticism if it declines to appeal. If the First Circuit affirms, then the government would ask the Supreme Court to review the case, and the Court will likely agree to do so.
Thanks to commenter ruuffles for the pointer.
UPDATE: I just noticed that Dale beat me to it; please post comments there.