Here are the issues presented in the case:
(1) Whether Section 3 of the Defense of Marriage Act (DOMA) violates the Fifth Amendment's guarantee of equal protection of the laws as applied to persons of the same sex who are legally married under the laws of their State; (2) whether the Executive Branch’s agreement with the court below that DOMA is unconstitutional deprives this Court of jurisdiction to decide this case; and (3) whether the Bipartisan Legal Advisory Group of the United States House of Representatives has Article III standing in this case.
The NYT provides an overview. They note - as do many - that the likely decisive Justice Kennedy focused on federalism question, not equal protection questions. Does the federal government have the power to decide what marriage is? The states clearly do because this falls under the reserved powers, especially the police powers. Has the federal government intruded on this power?
Some analysts suggest this means the case is likely to be decided on federalism grounds, not equal protection, which means it might not be quite the victory gay and lesbian groups were hoping for. The equal protection clause will not be made applicable to sexual orientation - as it is to race, gender, age and the rest.
Here's the Wall Street Journal's Live Blog of the DOMA arguments.
Here's Andrew Sullivan's analysis of the oral arguments.
And here's commentary from people smarter than me:
Tom Goldstein points out that a federalism ruling in Windsor makes the case for the plaintiffs in Hollingsworth stronger. California can decide for itself whether marriage can be same sex or not, and Proposition 8 said it couldn't. Presumably that means that the equal protection argument would not work. Unless the court argues the plaintiffs lack standing.
Jeffrey Toobin argues that the Supreme Court is not central to the direction same - sex marriage is heading, and the justices know it. He highlights the following: Toward the end of the argument, Roberts asked Roberta Kaplan, the lawyer for Windsor, “You don’t doubt that the lobby supporting the enactment of same sex-marriage laws in different states is politically powerful, do you?” Kaplan—somewhat improbably —denied it. Roberts fought back: “As far as I can tell, political figures are falling over themselves to endorse your side of the case.”
Andrew Cohen is concerned that not enough was said in the oral arguments about the history of anti-gay discrimination in the US. Thsi will not bode well for this court's reputation: "I think history will judge the Supreme Court, and by extension the rest of us, by what was not argued this week. The Court did not confront and condemn the discrimination at the core of these laws. It did not signal a willingness by the judiciary to stand up to the tyranny of the majority. And it did not even minimally force the laws' defenders to justify with facts their disparate treatment of same-sex couples. It was instead a court openly looking for a way out, which, in the end, makes you wonder what kind of court it is at all."