A majority of the Supreme Court's justices expressed skepticism today about the federal law defining marriage as between one man and one woman.
Today's arguments on DOMA marked the second straight day that the nation's highest court considered a high-profile case on gay marriage.
After considering a challenge to California's Proposition 8 ban on gay marriage Tuesday, the Supreme Court heard arguments today in a case seeking to overturn the 1996 law signed by President Bill Clinton that defined marriage as heterosexual and prevented gay couples from receiving federal marriage benefits. If the Supreme Court considers the merits of either case, it could issue a landmark ruling on gay marriage by the end of June.
Supporters of gay marriage saw an encouraging sign today.
Justice Anthony Kennedy, viewed as a key swing vote, appeared critical of the federal government's declining to recognize marriages that states have made legal.
Kennedy cited concerns about federalism, saying there was a "real risk" of the federal law running into conflict with a state's power.
"The question," Kennedy said, "is whether or not the federal government, under our federalism scheme, has the authority to regulate marriage."
The four liberal justices expressed similar concerns over federal power, as well as other concerns about equal protection of gay Americans under the law.
Justice Ruth Bader Ginsburg asked about a marriage that is recognized by the state but not the federal government. She pointed out that a couple that is legally married in a state might be denied marital deductions and Social Security benefits. "Your spouse is very sick, but you can't get leave," she said. "One might well ask, what kind of marriage is this?"
Paul Clement defended DOMA on behalf of the Bipartisan Legal Defense Group (BLAG), which is led by House Republicans.
"What gives the federal government the right to be concerned at all at what the definition of marriage is?" asked Justice Sonia Sotomayor.
Ginsburg asked Clement about the two kinds of marriage in states that allow gay marriage -- "the full marriage, and then this sort of skim milk marriage," in her words.
Clement said that one reason DOMA was passed was for "uniformity," so that the federal definition of marriage would be the same throughout the states.
Justice Elena Kagan attacked his position. Reading from a 1996 committee report that cited moral disapproval toward some behaviors. That suggested, she said, that Congress might have been motivated partially by animus.
Chief Justice John Roberts challenged that position.
"Eighty-four senators based their vote on moral disapproval?" he asked.
Roberts also suggested that gays and lesbians should not be considered a politically powerless "suspect class," requiring higher scrutiny for discrimination in laws. Roberts noted the recent sea change in public opinion on the issue of gay marriage.
"As far as I can tell, political figures are falling over themselves to endorse," Roberts said.
Unlike Tuesday's Prop 8 arguments, when lawyers and justices aired common disputes about gay marriage, today's DOMA proceedings involved less profound talk about the merits of gay marriage's legality. A major part of the discussion focused on how the case made its way to the Supreme Court, whether the court should even consider DOMA's merits and the odd legal "standing" issue of who was defending it.
After the Obama administration declared DOMA unconstitutional, a group of House Republicans stepped in to back its defense.
The justices dedicated 50 minutes to two threshold questions regarding whether the case has properly come before the Supreme Court. One question had to do with whether there was a real controversy before the court, given that the executive branch agreed that the law was unconstitutional. The other question concerned whether lawyers for House Republicans had the right to defend DOMA in court.
"Is there any case where all the parties agreed with the decision below and we upheld appellate jurisdiction?" Roberts asked. "This is totally unprecedented. You're asking us to do something we have never done before."
Justice Antonin Scalia showed no sympathy for the government's position that DOMA should be overturned.
"If we're in this new world, I don't want cases like this to come before the court all the time," he said.
The DOMA challenge was brought by Edie Windsor, an 83-year-old woman from New York who married Thea Clara Spyer in 2007. After Spyer's death in 2009, Windsor was denied an exemption of federal estate taxes.
DOMA has enraged gay-rights activists, some of whom have harbored resentment at Clinton for signing it into law in the first place.
Almost as soon as President Obama took office, activists urged the administration to oppose DOMA. In February 2011, they got their wish, as Attorney General Eric Holder announced in a letter to Congress that the Department of Justice would no longer defend DOMA in federal court.
The Obama administration has argued that DOMA should be overturned, while House Republicans have stepped in to defend it through BLAG and its attorney, Clement, George W. Bush's former solicitor general.
In his briefs, Clement argued that the federal government does not invalidate any state laws allowing gay marriage, but instead ensures that federal benefits are distributed uniformly throughout the states.
Current Solicitor General Donald B. Verrilli, who appeared before the court on Tuesday to weigh in against California's marriage ban, has argued that DOMA unfairly denies federal benefits to gay married couples.
Before considering the merits of DOMA, the court considered two threshold issues: whether it even has jurisdiction to hear the case given that the Obama administration believes DOMA should be overturned, and whether BLAG has legal "standing" to defend it. Both sides wanted the court to consider the merits of DOMA, so the court appointed Harvard law professor Vicki Jackson to argue the threshold issues.
On Tuesday, supporters and opponents of gay marriage gathered outside the Supreme Court to hold signs and make their voices heard. The justices struggled with the notion of extending marriage rights to gay couples, pressing lawyers on both sides of the Prop 8 case.
All eyes once again focused on Justice Kennedy, viewed as the court's key swing vote on gay marriage.
On Tuesday, he asked some conflicting questions on the issue of the lawyers arguing before him.
"The voice of these children is important," Kennedy said at one point, noting that children of gay couples want their parents' unions to be recognized as marriages.
But later he told the lawyer for gay couples challenging the ban that the issue was in "uncharted waters."
The court was considering these two potentially landmark gay-marriage cases as the politics of the issue shift by the day.
After Ohio Republican Sen. Rob Portman announced his support for gay marriage earlier this month, becoming the only current GOP senator to hold that position, a herd of Democratic senators have stampeded toward the marriage issue. Sens. Claire McCaskill, D-Mo., Mark Warner, D-Va., Jon Tester, D-Mont., and Mark Begich, D-Alaska, have all announced their support for gay marriage this week.
Public opinion, too, has shifted drastically on gay marriage in the last decade.
A recent ABC News/Washington Post poll, taken March 7-10, showed 58 percent of respondents in support of gay marriage, while 36 percent opposed it. That's nearly the opposite of public opinion on gay marriage in 2003, when ABC/Post polling showed 37 percent support and 55 percent opposition.