Historic arguments over same-sex marriage got underway before the U.S. Supreme Court on Tuesday, with justices drilling lawyers on opposing sides on the power of states to prohibit gay unions.
Justice Anthony Kennedy, considered a swing vote, pointed out that for centuries marriage was understood as between a man and a woman. He asked whether the public and scholars need more time to debate changes to marriage.
This definition has been with us for millennia. And it it's very difficult for the court to say, oh, well, we know better," Kennedy told Mary Bonauto, a lawyer representing same-sex couples.
But Kennedy also grilled John Bursch, a lawyer for states that ban gay marriage, asking how such prohibitions damage traditional marriages. Bursch argued that, absent the central rationale of raising children, same-sex marriage weakens the parents' commitment to remaining together if their own relationship breaks down.
Chief Justice John Roberts, a conservative, said gay couples seeking to marry are not seeking to join the institution of marriage.
"You're seeking to change what the institution is," Roberts said, The Associated Press reported.
But Roberts also questioned the states' argument, asking why bans weren't sexual discrimination.
Liberal justices Stephen Breyer and Sonia Sotomayor said states needed to show a compelling reason to deny it to a class of people, according to the AP. Breyer asked whether the nation needed more time to determine whether gay marriage was harmful to society.
Those early comments made it difficult to determine where the court was headed on the issue.
Tuesday's arguments marked the culmination of a debate that has roiled the nation for the better part of a decade. The legal showdown is the biggest regarding marriage rights since laws against interracial unions were struck down a half-century ago.
Across the country, a flurry of court decisions invalidated state bans on same-sex marriage. In the past 20 months alone, nearly 60 separate decisions have been issued in more than half the states.
Most cited a U.S. Supreme Court ruling from two years ago — written by Kennedy — that struck down a federal law that blocked the government from recognizing same-sex marriages in the states that allowed them.
The current case hinges on the Supreme Court's interpretation of the 14th Amendment to the U.S. Constitution, which guarantees equal protection and due process of law.
The court will consider whether the amendment prohibit states from blocking same-sex couples from getting married? Four federal appeals court have said it does.
But a fifth, the 6th U.S. Circuit Court of Appeals, based in Cincinnati, upheld laws banning marriage for gay couples in Kentucky, Michigan, Ohio, and Tennessee. Those states argue that preserving traditional marriage promotes family stability and encourages opposite-sex couples — who can produce children — to get married.
The opponents say the people, not the courts, have the right to define marriage.
Advocates for same-sex couples, meanwhile, argue that the courts must step in to stop states from violating people's constitutional rights.
While lawyers spent the morning answering questions from the justices, raucous crowds of demonstrators, most advocating gay marriage rights, gathered outside the Supreme Court building, waving flags, cheering, chanting and giving speeches.
A small but vocal minority of opponents tried to outshout the supporters.
Nationwide, popular sentiment is on the side of gay couples, with a clear majority of Americans supporting same-sex marriage rights — 59 percent in the latest NBC News/Wall Street Journal poll. A total of 36 states now permit it. In most of those cases, the outcomes were determined by judges, not by legislatures or voters.
Seventeen states have filed friend-of-court briefs arguing that they, not the federal courts, should determine who can marry whom. Another 19 states are urging the Supreme Court to declare the state bans unconstitutional.
The Obama administration wants the court to find the state bans unconstitutional.
The justices set aside two and a half hours Tuesday to ask lawyers on both sides two central questions.
The first is whether the 14th Amendment require a state to license a marriage between two people of the same sex. The second is whether the 14th Amendment requires a state to recognize a marriage between two people of the same sex when their marriage was lawfully licensed and performed out of state.
There are two possible outcomes when the court issues its decision, expected by late June.
If the court agrees with states who say they should be free to decide who can get married within their borders, then nation would remain divided, with some states choosing to permit it and others banning it. in the scenario, same-sex marriage would remain legal in the 16 states that have adopted it by popular vote, by vote of a state legislature, or by state court decision.
If the court sides with gay couples, and rules that states cannot refuse to issue marriage licenses to gay couples, then 14 existing state bans would be struck down and same-sex marriage would become law of the land, bringing the the legal dispute to an end.
After Tuesday's arguments, same-sex marriage advocates descended the Supreme Court building's steps to the cheers of supporters.
Bonauto said the session itself was an historic step. "The justices asked tough questions today, but that's their job. But we're very grateful to be here," she said.
— with Kasie Hunt, Jon Schuppe and The Associated Press.