WASHINGTON (USA TODAY) -- A slim majority of Supreme Court justices voiced skepticism Wednesday about a federal law that denies benefits to gay and lesbian married couples, signaling they may be willing to overturn it.
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But the court's conservatives, led emphatically by Chief Justice John Roberts, defended the law, a clear sign that any decision likely would come by a 5-4 margin.
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And like Tuesday, when the court appeared disinclined to issue a far-reaching decision on California's same-sex marriage ban, it was not clear whether the justices felt the case was even properly before them. That could result in no substantive ruling at all.
After nearly two hours of debate, it was clear that Justice Anthony Kennedy, the perennial swing vote, held the balance of power on the court. He questioned whether the federal government lacked the authority to deny benefits to couples legally married in their states.
At issue is the Defense of Marriage Act, a 1996 law passed overwhelmingly by Congress and signed by President Clinton that defines marriage as between a man and a woman. At the time, no states had legalized same-sex marriage, but now nine states and the District of Columbia have done so - and legally married gay couples are being denied federal spousal benefits.
Lawyers on both sides of the issue faced pointed questioning from nearly the entire panel of justices who took issue with a range of matters, from the federal government's decision to no longer defend the law - declared unconstitutional in lower federal courts - to the authority of the House Republican leadership to take up the law's defense.
"You are asking us to do something that we have never done before," Roberts told U.S. Deputy Solicitor General Sri Srinivasan, referring to the government's decision not to defend the law while continuing to enforce it. "It is totally unprecedented."
Citing what he described as a "new regime" at the Justice Department under President Obama, Justice Antonin Scalia said that there was "no rational argument" for the government's decision not to defend the existing law.
"I don't want these cases to come before this court all the time," Scalia said, suggesting that the decisions on whether to defend or enforce existing law were part of a "new world."
If the Obama administration had decided that the marriage law was unconstitutional, Roberts asked at one point, "Why doesn't he have the courage of his convictions" and simply not enforce it
Former U.S. solicitor general Paul Clement, representing Republican House leaders, faced equally sharp questions about the congressional group's standing to intervene.
"The House is the proper authority to defend (the law)," Clement told the justices.
The questions on the court's authority in the matter were debated for nearly an hour before the two sides moved to the merits of the case. It's possible the justices ultimately will sidestep a far-reaching decision when they issue their ruling, most likely in late June.
The case before the court involves Edith Windsor, an 83-year-old New York widow who married her longtime partner, Thea Spyer, in 2007. When Spyer died in 2009, Windsor was socked with a $363,000 estate tax bill that she would have avoided if Thea had been "Theo," because heterosexual spouses can transfer wealth tax-free.
Now in failing health but a hero within the gay rights community, Windsor came to court Wednesday to hear her lawyer present her case. And not only her lawyer - the federal government also takes her side, which is both a benefit and a potential curse.
On Tuesday, the court debated California's Proposition 8, a ballot initiative that banned same-sex marriage in the state. The justices could have avoided taking the Proposition 8 case, but they were forced to tackle DOMA because it had been declared unconstitutional at the lower-court level. They chose from among several overlapping cases, including challenges to the law from New England, New York and California.
The plaintiffs in those cases - married same-sex couples, widows and widowers in states where gay marriage is or previously was legal - are seeking the same federal benefits accorded opposite-sex couples, from joint tax returns to survivor benefits.
The Defense of Marriage Act has two main sections, only one of which - defining marriage in federal laws as between a man and a woman - is being contested. Because of it, benefits and programs enjoyed by opposite-sex couples aren't available to gays and lesbians under federal employment, health, tax and other laws. The other provision shields states from having to recognize gay marriages from other states.
Attorney General Eric Holder announced in 2011 that the Obama administration considered DOMA unconstitutional and no longer would defend it in court. Into the breach stepped House Republicans, who argued - to no avail in lower courts - that the law saves needed federal resources and ensures they are distributed equally among the states.
At last count, there were 1,138 provisions in federal laws that listed marital status as a factor in determining benefits, rights and privileges. The list, prepared by the Government Accountability Office, was most recently updated in 2003.
The most prevalent are tax laws. Despite their marriage certificates, gay and lesbian spouses cannot get tax-free health benefits from their employers. That alone costs them about $1,000 a year on average, says Gary Gates, a demographer who studies gay and lesbian trends at the UCLA School of Law's Williams Institute.
Gays and lesbians can't file joint federal tax returns, as heterosexual married couples can, which often saves families thousands of dollars. If gays or lesbians divorce, any alimony is considered a gift subject to taxation, while for opposite-sex couples, it's tax-free. And when a spouse dies, the widow or widower is liable for inheritance taxes; heterosexual couples enjoy a marital deduction.