1 of 8. People wait in line, in the hopes of being seated, to hear the arguments in the case against the Defense of Marriage Act (DOMA) at the U.S. Supreme Court in Washington, March 27, 2013. 
 
 WASHINGTON | 
 
 WASHINGTON (Reuters) - For the second day running, the Supreme Court convened on Wednesday to tackle the issue of gay marriage, this time to hear arguments over a law that denies federal benefits to legally married same-sex couples. 
 
 Almost two hours of oral argument will be heard by the court on the Defense of Marriage Act (DOMA). The nine justices heard arguments on Tuesday on the constitutionality of California's Proposition 8 ban on gay marriage. 
 
 In those arguments, the justices displayed a reluctance to rule broadly on the right to marry for gays and lesbians, suggesting the court may be similarly cautious about DOMA. 
 
 Rulings in both cases are expected by the end of June. 
 
 The cases come before the court as polls show growing support among Americans for gay marriage but division among the 50 states. Nine states recognize it; 30 states have constitutional amendments banning it and others are in-between. 
 
 DOMA limits the definition of marriage as between a man and a woman. It permits benefits such as Social Security survivor payments and federal tax deductions only for married, opposite-sex couples, not for legally married same-sex couples. 
 
 President Bill Clinton signed DOMA into law in 1996 after it passed Congress with only 81 of 535 lawmakers opposing it. Clinton, a Democrat, earlier this month said that times have changed since then and called for the law to be overturned. 
 
 The atmosphere outside the courthouse was more subdued than on Tuesday, when thousands of raucous protesters filled the sidewalks. A largely pro-gay marriage crowd of several hundred held signs and waved American flags. 
 
 Hundreds more waited patiently in line for a chance at the handful of seats in the courtroom allocated to the public. 
 
 "It was pretty cold," said Liz Ghandakhy, 28, a lawyer who got in line at 5:30 a.m. Tuesday and slept overnight on the sidewalk. "It's one of the greatest civil rights cases of our time." 
 
 A few minutes later, a beaming Ghandakhy was headed inside. 
 
 The DOMA case is about whether Edith Windsor, who was married to a woman, should get the federal estate tax deduction available to heterosexuals when their spouses pass away. 
 
 Windsor's marriage to Thea Spyer was recognized under New York law, but not under DOMA. When Spyer died in 2009, Windsor was forced to pay federal estate tax because the federal government would not recognize her marriage. She later sued the government, seeking a $363,000 tax refund. 
 
 Windsor's lawyers say the federal government has no role in defining marriage, which is traditionally left to the states. 
 
 Lower courts have ruled in her favor. 
 
 The roughly 133,000 gay couples nationwide, married in one of the nine states where it is legal, are not recognized as married by the federal government, Windsor's supporters say. 
 
 Various groups are calling for DOMA to be struck down, such as the Business Coalition for DOMA Repeal, whose members include Marriott International Inc, Aetna Inc, eBay Inc, and Thomson Reuters Corp, the corporate parent of the Reuters news agency. 
 
 OBAMA TURNS BACK ON DOMA 
 
 The Obama administration has agreed with Windsor that the section of law that defines marriage violates the U.S. Constitution's guarantee of equal protection under the law. The Justice Department has thus declined to defend the statute, as it normally would when a federal statute is challenged. 
 
 That has left a legal group acting on behalf of the Republican-dominated U.S. House of Representatives, known as the Bipartisan Legal Advisory Group, or BLAG, as the party defending the federal law. Its lawyer, Paul Clement, will argue that there are several reasons to support Congress's decision to enact DOMA. 
 
 Noting the strong bipartisan support the law attracted when enacted, Clement said in court papers that a move to strike it down as unconstitutional "would be wholly unprecedented." 
 
 Before the court reaches that bigger question, preliminary matters could prevent a decision. One is whether BLAG has legal standing. If such a procedural issue prevents the court from deciding the case on the merits, Windsor would win her refund. 
 
 Yet DOMA would stay on the books in states where courts have not ruled on it. Further litigation would likely ensue. 
 
 (Reporting by Lawrence Hurley and David Ingram; Editing by Kevin Drawbaugh and Eric Beech) ||||| Story highlights The Justice Department files first in a series of legal briefs involving two big cases 
 
 Supreme Court will hear arguments next month on Defense of Marriage Act 
 
 Lawyers for House GOP say they should be able to defend the marriage law in court 
 
 U.S. still deciding whether to intervene in second case involving California law 
 
 In a preview of a major constitutional showdown at the Supreme Court over same-sex marriage, the Obama administration said on Friday that a federal law denying financial benefits to legally wed gay and lesbian couples is unconstitutional. 
 
 The Justice Department filed the first of a series of briefs in a pair of cases dealing with the multilayered issue, outlining the executive branch's positions. 
 
 The high court will hear oral arguments next month on the Defense of Marriage Act (DOMA), a 1996 congressional law that says for federal purposes, marriage is defined as only between one man and one woman. 
 
 That means federal tax, Social Security, pension, and bankruptcy benefits, and family medical leave protections -- do not apply to gay and lesbian couples. 
 
 This case deals with Edith "Edie" Windsor, forced to assume an estate tax bill much larger than other married couples would have to pay. Because her decades-long partner was a woman, the federal government did not recognize the same-sex marriage in legal terms, even though their home state of New York did. 
 
 But now, led by President Barack Obama's recent political about-face, the administration opposes the law. 
 
 "Moral opposition to homosexuality, though it may reflect deeply held personal views, is not a legitimate policy objective that can justify unequal treatment of gay and lesbian people" contained in the DOMA law, Solicitor General Donald Verrilli said in the Justice Department's legal brief. 
 
 The separate case from California deals with Proposition 8, a 2008 voter-approved referendum banning same-sex marriage. This after the California high court had earlier concluded same-sex couples could legally wed. That case too will be heard in late March. 
 
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 Though not a party in the California case, government sources say the Justice Department was prepared next week to file an "amicus" or supporting brief asserting a constitutional right to same-sex marriage, and that Proposition 8 should be struck down as a violation of constitutionally guaranteed "equal protection" of the laws. 
 
 Those sources say Obama was expected to make the final call on whether to intervene in the state dispute. 
 
 "I have to make sure that I'm not interjecting myself too much in this process, particularly when we're not a party to the case," Obama said Wednesday in an interview with CNN affiliate KGO-TV in San Francisco. 
 
 Of more immediate concern was the DOMA fight, where the administration is squarely involved. But a tricky gateway or "jurisdictional" question threatens to stall any final consideration of the law's constitutionality. That was the focus of much of the Friday legal papers. 
 
 The DOMA law will be defended by House Republicans, after Obama concluded the law was unconstitutional. 
 
 Traditionally, that role would fall to the solicitor general's office. But Obama, in an election-year stunner, said last May that he supported same-sex marriage. 
 
 The president had already ordered Attorney General Eric Holder not to defend DOMA in court. That raised the question of whether any party could rightfully step in and defend the law. 
 
 Besides the constitutional issue, the justices had specifically ordered both sides to argue a supplemental question: whether congressional Republicans -- operating officially as the Bipartisan Legal Advisory Group of the U.S. House of Representatives -- have "standing" or legal authority to make the case. 
 
 Lawyers representing the House GOP said Friday that they should be able to take the lead and defend the law, since both Windsor and the Obama administration are taking the same legal position. 
 
 "Without the House's participation," said attorney Paul Clement, representing House leaders, "it is hard to see how there is any case or controversy here at all. Both Ms. Windsor and the executive agree that DOMA is unconstitutional and that Ms. Windsor was entitled to a [tax] refund. And the lower courts granted them all the relief they requested. Only the House's intervention provides the adverseness that Article III [federal court jurisdiction] demands." 
 
 But the Justice Department said it alone should present the government's case. 
 
 "House Republicans lack "any basis for supplanting the executive branch's exclusive role in representing the United States' interests in this litigation, and has no interests of its own that would satisfy" federal court scrutiny, said administration lawyers. 
 
 Windsor's legal team also said the House leaders could defend DOMA, at least partially, suggesting the woman wants ultimate resolution on the constitutional questions as soon as possible. 
 
 "I was devastated by the loss of the great love of my life, and I was also very sick, then had to deal with pulling together enough money to pay for the taxes," the 83-year-old Windsor told CNN recently. "And it was deeply upsetting." 
 
 That fundamental unfairness, as Windsor and her supporters see it, is at the center of DOMA legal fight. 
 
 In November, three states -- Maryland, Washington, and Maine -- approved same-sex marriage, adding to the six states and the District of Columbia that already have done so. Minnesota voters also rejected an effort to ban such unions through a constitutional amendment. 
 
 As more states legalize same-sex marriage, one of the key questions the justices may be forced to address is whether a national consensus now exists supporting the idea of expanding an "equal protection" right of marriage to homosexuals. 
 
 A bill known as the Respect for Marriage Act is working its way through Congress and would repeal DOMA. 
 
 That law does not prohibit states from allowing same-sex marriages, but it also does not force states to recognize them from other states. Most of the current plaintiffs are federal workers, who are not allowed to add their spouses to health care plans, and other benefits. 
 
 Many other states, including New Jersey, Illinois, Delaware, Rhode Island and Hawaii, have legalized domestic partnerships and civil unions for such couples -- a step designed in most cases to provide the same rights of marriage under state law. 
 
 But other states have passed laws or state constitutional amendments banning such marriages. California's Proposition 8 is the only such referendum that revoked the right after lawmakers and the state courts previously allowed it. That makes it a somewhat unique legal case for review by the justices. 
 
 The DOMA cases are U.S. v. Windsor (12-307) and Bipartisan Legal Advisory Group of the U.S. House of Representatives v. Windsor (12-785).
– The Supreme Court heard arguments on California's Prop 8 yesterday; today, the federal Defense of Marriage Act is on the docket. What to expect: What is today's case about? DOMA defines marriage as a union between one man and one woman, meaning that gay couples who legally wed in states that allow gay marriage are denied federal benefits. The high court must decide if the federal government can constitutionally do that. The specific case being considered involves Edith Windsor, 83, who married partner Thea Spyer in 2007. When Spyer died, Windsor was hit with a $363,000 estate tax bill because their marriage wasn't recognized. She's suing for a refund. Will Windsor be there? She is expected to be, but her health is declining, USA Today reports. How many people are affected? There are about 133,000 married gay couples not currently recognized by the feds, Reuters reports. The Washington Post points out that while yesterday's case involved people not yet married, today's involves people who are. What are the tax implications? If the Supreme Court strikes down DOMA, taxes for some same-sex couples might actually go up, Politico reports. The so-called "marriage penalty" means that when couples whose incomes are similar file a joint tax return, they don't get as many tax breaks as they would have had they filed separately. That "penalty" could end up applying to gay couples who currently skirt it. How will yesterday's session affect today's? It may not. Yesterday's case could potentially involve a much broader ruling; the court could theoretically strike down Prop 8 and also extend gay marriage rights to all states. But the justices seemed wary of doing that. So, Reuters notes, that case may have little bearing on today's, since DOMA is a much narrower question. And, as NPR reports, it's also "a much clearer question," and the themes that come up today aren't likely to be similar to yesterday's. The only two expected outcomes: Is DOMA constitutional or not? When is a decision expected? Late June. A ruling on the Prop 8 case is expected at the same time. Is there a possibility there won't be a decision? Yes. The Obama administration refuses to defend DOMA in court, so House Republican leaders are defending it. The court could decide that those members have not suffered an injury that would allow them to bring the case, and could thus decide not to rule on it.