One of the attorneys in the California Proposition 8 case, David Boies (center), speaks outside the Supreme Court as he's surrounded by plaintiffs in the case, couples Paul Katami (from left) and Jeff Zarrillo, and Sandy Stier and Kris Perry. Mark Wilson/Getty Images hide caption

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Chief Justice Margaret Marshall asks petitioner to explain a point during arguments before the Supreme Judicial Court in Boston in 2005. George Rizer/AP hide caption

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A pro-gay-marriage protester stands in front of the Supreme Court on Tuesday, the first of two days of oral arguments on challenges to laws that limit the definition of marriage to unions of a man and a woman. Karen Bleier/AFP/Getty Images hide caption

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Edith Windsor in her New York City apartment in December 2012. Next week, the U.S. Supreme Court hears her challenge to the 1996 Defense of Marriage Act. Richard Drew/AP hide caption

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Edith Windsor, 83, is asking the Supreme Court to strike down the federal Defense of Marriage Act. When Windsor's female spouse died, the federal government, acting under DOMA, required Windsor to pay estate taxes that she would not have owed if her spouse had been a man. Richard Drew/AP hide caption

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