The U.S. Supreme Court announced Friday that for the first time it will tackle the issue of same-sex marriage. Defying most expectations, the justices said they will examine two cases, presenting the possibility that the court could decide all the basic issues surrounding same-sex marriage in one fell swoop.

As expected, the court said it will rule on the constitutionality of the Defense of Marriage Act, known as DOMA. The case tests whether the federal government can deny federal benefits to legally married same-sex couples — benefits that are automatically granted to heterosexual couples.

Less expected was the court's decision to review California's ban on same-sex marriage, known as Proposition 8. That case potentially could lead to a decision on whether gay couples have a constitutional right to marry.

The California case involves a ban to gay marriage, enacted by referendum in 2008 and subsequently struck down by a federal appeals court on narrow grounds.

Opponents of gay marriage appealed to the Supreme Court, contending that states are free to limit marriage to unions between a man and a woman. The justices said they would hear arguments on that question, but they also called for arguments as to whether gay marriage opponents have the right to be in court at all, since California is no longer defending the ban.

Law professor Stephen Vladeck of American University says the decision to take the Proposition 8 case shows the justices are "finally ready to tackle this head-on ... a good sign for those who support gay marriage."

Some gay-rights activists, however, are worried that this may be too early to bring the constitutional issue to the justices.

Mary Bonato of GLAD, the Gay and Lesbian Advocates and Defenders, said last week she "can't help but be concerned" about the prospect of the court addressing Proposition 8 right now. "I think it's extremely important we engage all the branches of government and the all-important court of public opinion," she said, "so that the Supreme Court would have a high comfort level that they are not too far ahead of public opinion."

Defense Of Marriage Act Case

The DOMA case is more limited because it involves only a federal law that refuses federal benefits to same-sex couples who are legally married.

Nine states and the District of Columbia now permit same-sex marriage, but the federal government does not recognize those unions. Thus, a wide variety of spousal benefits that are accorded to heterosexual couples under some 1,000 federal statutes and programs are denied to legally married same-sex couples. Such benefits include everything from Social Security to health insurance for spouses of federal employees.

The test case that the Supreme Court said it will review involves a New York couple, Edith Windsor and Thea Spyer, who had been together for 42 years prior to their marriage in 2007. When Spyer died, however, the federal government, acting under DOMA, required Windsor to pay $363,000 in estate taxes that she would not have owed if her spouse had been of the opposite sex.

"I brought my case against the government," Windsor said, "because I couldn't believe that our government would charge me $350,000 because I was married to a woman and not a man."

Windsor won in the lower courts. Indeed, in the past couple of years, 10 courts, with judges appointed by both Democratic and Republican presidents, have ruled that DOMA is unconstitutional.

Typically, when a court says a federal statute is unconstitutional, the federal government appeals to the Supreme Court to change the outcome. But after initially defending DOMA in the courts, the Obama administration made a highly unusual U-turn, and instead urged the Supreme Court to strike it down.

At that point, the House Republican leadership hired its own lawyer to defend the law. So when the case is argued, probably in March, it will be that lawyer — former Bush administration Solicitor General Paul Clement — who will be defending DOMA, while the Obama administration will be urging the court to strike down the statute.

These twists and turns apparently have caused the justices some concern as to whether they have the jurisdiction to decide the case when the federal government is no longer defending the law as constitutional. So the court has ordered the lawyers to also present arguments as to whether the Republican congressional leadership has standing to defend DOMA in place of the Obama administration.

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