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Advocates on both sides hope for Supreme Court clarity on same-sex marriage

The Supreme Court's decision to review two landmark cases that deal with same-sex marriage could determine the future of gay rights in all 50 states. NBC's Pete Williams reports.

New in this version: Adds legal analysis

Updated at 6:50 p.m. ET: The Supreme Court's announcement Friday that it will take up two same-sex marriage cases this term gave advocates on both sides something to cheer about.

The court picked cases involving two measures that defined marriage as being between a man and a woman: the 1996 Defense of Marriage Act, a federal law, and California's Proposition 8, a ballot initiative approved by state voters in 2008.

Nearly two decades of legal skirmishing over the question has left supporters and opponents of same-sex marriage alike hoping for clarity from the Supreme Court, which has never before considered the topic.

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"We are delighted that the nation's highest court will decide whether to uphold the will of more than 7 million Californians who voted to preserve the unique definition of marriage as only between one man and one woman," said Andy Pugno, general counsel of Protect Marriage, which sponsored Proposition 8 and petitioned the court for a hearing after it was struck down as unconstitutional by a federal court.

US Supreme Court to take up same-sex marriage issue

"Arguing this case before the Supreme Court finally gives us a chance at a fair hearing, something that hasn't been afforded to the people since we began this fight," Pugno said.

At the same time, California Attorney General Kamala Harris, who opposed enactment of the initiative, also welcomed the news, saying that "for justice to prevail, Proposition 8 must be invalidated so that gay and lesbian families are finally treated with equality and dignity."

Rick Jacobs, founder of Courage Campaign, a California group that campaigned vigorously against Proposition 8, said the Supreme Court hearing would hasten the day when the law would "catch up with the American public."

Supreme Court to hear gay marriage cases: Your view

"Sooner than later, no one will care about loving gay and lesbian couples marrying any more than they care about their straight counterparts doing so," Jacobs said in a statement. "Each day of delay brings more suffering and hardship."

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Edith Windsor challenged the Defense of Marriage Act after she received a $363,000 estate tax bill when her spouse died in 2009.

The case challenging the Defense of Marriage Act, which President Bill Clinton signed into law in 1996, was brought by Edie Windsor, 83, of New York, who was assessed a $363,000 estate tax bill after Thea Spyer, her partner of 44 years, died in 2009. 

The Defense of Marriage Act, or DOMA, made it illegal for the State of New York to recognize the women's marriage in Canada. If Spyer had been married to a man, the estate she left Windsor wouldn't have been liable for taxes.

"When Thea and I met nearly 50 years ago, we never could have dreamed that the story of our life together would be before the Supreme Court as an example of why gay married couples should be treated equally and not like second-class citizens," Windsor said Friday. 

"While Thea is no longer alive, I know how proud she would have been to see this day," she added. "The truth is, I never expected any less from my country."

Rea Carey, executive director of the National Gay and Lesbian Task Force, said the cases "present the Supreme Court with a monumental opportunity to affirm our Constitution's promises of liberty, equality and human dignity."

"The journey is not finished, for as long as DOMA remains intact, then true equality remains out of reach," she said. "The clock is ticking on DOMA — it's time the Supreme Court strike down DOMA and Proposition 8, once and for all."

But Tony Perkins, president of the Family Research Council, a conservative Christian advocacy group, said he was confident that the court "will recognize that DOMA is supported by numerous legitimate legislative purposes — all of which are consistent with our principles of federalism."

"The argument that the authors of our Constitution created or even implied a 'right' to redefine 'marriage' lies outside our constitutional law," Perkins said. "Additionally, we believe that the people's vote on Proposition 8 should be respected."

The court has never before waded into the highly contentious issue of same-sex marriage.

"This is a monumental action by the Supreme Court, because we know they're going to say something about gay marriage for the first time ever," said Tom Goldstein, publisher of the closely watched SCOTUSBlog. (SCOTUS is shorthand for Supreme Court of the United States.)

Michael Klarman, a constitutional law professor at Harvard University, said he thought it was likely that the court would invalidate DOMA.

"There is some chance the vote won't even by 5-4, as some conservative justices who don't necessarily think there is a right to same-sex marriage will be troubled by the federalism implications of Congress' defining marriage rather than deferring to the states on this issue," Klarman, author of the forthcoming "From the Closet to the Altar: Courts, Backlash, and the Struggle for Same-Sex Marriage," told NBC News by email.

As for the Proposition 8 case, Klarman was less willing to make a prediction, saying the justices could "reject the argument that same-sex marriage is constitutionally protected, they could accept that argument or they could narrowly affirm the 9th Circuit and invalidate what California has done in a way that has no implications for any other state."

He said the last option was unlikely, which means "I would guess they will either broadly embrace a right to same-sex marriage or reject it."

Arguments are expected in March, with rulings likely by June.

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