Chief Justice John Roberts (Photo credit: Steve Petteway, Collection of the Supreme Court of the United States)

Today’s argument in the U.S. Supreme Court over the Defense of Marriage Act sounded at times as if President Obama was on trial for enforcing the law even though he considers it unconstitutional. At other times, it sounded like Congress was on trial, for attempting to cloak its moral disapproval of gay people under the guise of seeking “uniformity.” And at the end of two hours, LGBT legal activists seemed cautious but optimistic that there are five votes to find DOMA unconstitutional.

It was the second and final day of two historic sessions at the nation’s highest court to hear oral arguments in cases challenging the federal law denying recognition of marriage licenses granted to same-sex couples and challenging a state law banning same-sex couples from obtaining marriage licenses.

Wednesday’s case, U.S. v. Windsor, posed the question of whether Section 3 of DOMA violates the equal protection clause of the Fourteenth Amendment. New York lesbian Edith Windsor filed the lawsuit with the help of the ACLU when the federal government demanded she pay more than $360,000 in estate taxes after her same-sex spouse died. Surviving spouses in male-female marriages do not have to pay estate taxes.

The first 50 minutes of the two-hour argument was given to a discussion of whether the case was properly before the court, given procedural questions. On the issue of whether DOMA’s constitutionality, former George W. Bush Solicitor General Paul Clement, an attorney hired by the Republican-led Bipartisan Legal Advisory Group (BLAG), said the Congress, in passing the law in 1996, did not discriminate against gays but simply decided to define the term “marriage” “solely for federal law” in order to ensure “uniformity” in the deliverance of benefits.

“It’s rational for Congress to say its treating same-sex couples in New York the same as same-sex couples in Nebraska,” said Clement.

That assertion did not go unchallenged.

Justices Sonia Sotomayor, Elena Kagan, Stephen Breyer, Anthony Kennedy, and Ruth Bader Ginsburg all questioned Clement on it.

“What gives the federal government the right to be concerned at all about the definition of marriage?” asked Sotomayor, noting that marriage has always been considered an area of state law. She suggested members of Congress appeared to create a law to disfavor a “class they don’t like.”

When Clement suggested Congress was helping the states by putting the issue on “pause” and letting the states work through the democratic process in deciding the law in each state, Kennedy noted that DOMA seemed instead to be “helping states if they do what [members of Congress] want them to do.”

Justice Ginsburg said DOMA appears to affect same-sex couples by turning their marriages into a sort of “skim milk,” in comparison to whole milk version enjoyed by male-female couples.

Justice Kagan perhaps hit the hardest note when she said the record of House proceedings around DOMA in 1996 seemed to indicate Congress “had something else in mind than uniformity….something that’s never been done before.” She quoted a passage of the House report that said that DOMA was intended to express “moral disapproval” of marriage for same-sex couples.

“That’s a pretty good red flag,” said Kagan.

Clement seemed to be caught off guard by the excerpt. “Does the House Report say that?”

The challengers of DOMA appeared off guard at times, too.

Chief Justice John Roberts asked both Solicitor General Donald Verilli and plaintiff’s attorney Roberta Kaplan whether it would be permissible for Congress to adopt a definition for federal purposes that included gay couples, rather than excluded them.

Verilli said the House Report excerpt “makes glaringly clear” that DOMA was intended to exclude lawfully married same-sex couples.

“Are you saying that 84 senators were motivated by animus?” asked Chief Justice Roberts in follow-up to both Verilli and Kaplan.

Both Verilli and Kaplan clearly avoided saying that think DOMA was motivated by animus.

“It could have been a lack of reflection or an instinctive response,” said Verilli. But, he added emphatically, “Section 3 discriminates and it’s time for this court to recognize that discrimination cannot be reconciled with our fundamental commitment to equal protection of the law.”

But it was during questioning about the procedural matters that Roberts and other conservative justices hammered on what came across as much as a political jousting as it was a legal matter.

Roberts wondered why President Obama didn’t have “the courage of his convictions” that DOMA was unconstitutional and “instead, wait until the Supreme Court” rules it so.

Justice Samuel Alito said he thought it odd that President Obama would continue to enforce DOMA “until the court tells him to stop.”

Justice Breyer commented that the president has an “obligation” to faithfully execute the laws, whether he likes them or not.

Jon Davidson, legal director for Lambda Legal, said he was “very encouraged” by the argument.

“When it comes to the merits, I think there are at least five justices who are prepared to strike down Section 3 of DOMA,” he said. “One of the things that Justice Ginsburg said at the end, about the beginning of the sex discrimination cases, the court did strike down laws that discriminated based on sex based on rational basis, and saw it as discrimination.”

Mary Bonauto, head of civil rights for Gay & Lesbian Advocates & Defenders, said she thought the questioning was “vigorous” on the procedural issue of standing. On the issue of DOMA’s constitutionality, she said she thought Justice Kagan “called out” the discriminatory statement in the House report.

“Overall, they were asking the right questions and the right themes were in play,” said Bonauto.

Jenny Pizer, a Lambda Legal attorney who followed the case at the three-week trial in San Francisco, said she thought it was clear that the argument of “uniformity” made “no sense at all.”

“It was surprising to me the suggestion from some of the conservative justices that the administration should not enforce laws when they have questions about constitutionality or have a view of constitutionality different from previous administrations have said. That seems immensely impractical,” said Pizer.

“One thing that did seem clear yesterday and today,” said Pizer, “is that we’re witnessing a moment of recognition of anti-gay discrimination and the government trying to come to terms with how it should change. Perhaps we shouldn’t be that surprised that some justices are resistant to addressing the merits of question, but the justices are particularly well situated to address them.”

Yesterday’s argument was over the constitutionality of Proposition 8, California’s voter-approved ban on marriage licenses for same-sex couples. The court heard 80 minutes of argument in Hollingsworth v. Perry over whether it should find California’s ban on same-sex marriage unconstitutional.

In both cases, both sides see Justice Anthony Kennedy as the most likely justice to provide a fifth vote for the winning side. But Tuesday’s argument in the Proposition 8 case left many speculating that the court may decide that opponents of marriage quality did not have proper legal standing to appeal the case.

Legal standing was an issue in the Windsor case, too, because the Obama administration appealed the Second Circuit U.S. Court of Appeals ruling that DOMA violates the equal protection clause of the constitution. A party bringing an appeal must show it is injured by the lower court holding.