President Obama Explains Legal Argument for Same-Sex Marriage

Pablo Martinez Monsivais/AP Photo

President Obama today strongly suggested that his interpretation of the Constitution does support a fundamental right to same-sex marriage, even if he didn't put that argument in writing before the Supreme Court in a legal brief against California's Proposition 8.

"What we've said is that same-sex couples are a group, a class that deserves heightened scrutiny, that the Supreme Court needs to ask the state why it's doing it, and if the state doesn't have a good reason it should be struck down," Obama said today at an impromptu news conference in the White House briefing room. "That's the core principle, as applied to this case.

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"The court may decide that if it doesn't apply in this case, it probably can't apply in any case," he said. "There is no good reason for it. … If I were on the court, that would probably be the view that I'd put forward."

On Thursday, the Justice Department asked the Supreme Court to strike down the California ban on same-sex marriage but stopped short of calling for a fundamental right to marriage in every state under the Constitution.

The administration argued on paper that California's Proposition 8 violates the equal protection clause of the Constitution, noting that state extends all of the rights and responsibilities of marriage to gay and lesbians, but forbids them the designation of "marriage."

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The brief suggested that if the court were to agree with the administration's position, gay marriage laws in seven other states could be in jeopardy. Those states - Delaware, Hawaii, Illinois, Nevada, New Jersey, Oregon and Rhode Island - offer same-sex couples access to civil unions, which carry the same package of legal benefits as marriage without the name.

"The specific question presented before the court right now is whether Prop 8 and the California law is unconstitutional. And what we've done is we've put forward a basic principle which applies to all equal protection cases," Obama said today.

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"Whenever a particular group is being discriminated against, the court asks the question, what's the rationale for this, and it better be a good reason, and if you don't have a good reason we're going to strike it down," he said. "When the Supreme Court essentially called the question by taking this case about California's law, I didn't feel like that was something that this administration could avoid."

Experts say the administration's legal argument to the Supreme Court on Prop 8 reflects Obama's recognition that the court prefers to move incrementally on major social issues and is unlikely to approve of a sweeping 50-state solution at a time when 39 states still ban same-sex marriage.

ABC News' Ariane de Vogue contributed reporting.