Supporters and opposers of same-sex marriages gather outside the US Supreme Court on April 28, 2014 in Washington, DC.National Journal

This article is from the archive of our partner National Journal

The Supreme Court divided along traditional partisan lines Tuesday over a historic case that could make same-sex marriage legal in every state.

Justice Anthony Kennedy, who almost certainly will cast the deciding vote in the case, gave same-sex marriage supporters some reasons to be optimistic—but only cautiously.

The Court heard two and a half hours of oral arguments Tuesday in four consolidated cases, challenging laws in Kentucky, Michigan, Ohio, and Tennessee that ban same-sex marriage, refuse to recognize same-sex marriages from other states, or both. Same-sex couples say those laws violate the 14th Amendment of the Constitution.

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The arguments were interrupted after roughly 45 minutes by a protester, who could be heard screaming that homosexuality is "an abomination" for several minutes even after guards removed him from the courtroom.

Kennedy opened by questioning whether it would be appropriate for the Court to discard a definition of marriage that "has been with us for millennia."

Kennedy's later questions, though, touched on many of the same concerns he cited in decisions upholding gay rights—including the children of same-sex couples and the "dignity" conferred by marriage.

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And while the Court's conservative bloc continued to argue that same-sex marriage is too new to confer as a constitutional right, Kennedy noted that if the Court does rule in favor of same-sex marriage, its decisions on gay rights would have followed roughly the same time line as the rulings that led it to strike down bans on interracial marriage.

"Haven't we learned a tremendous amount ... just in the last 10 years?" Kennedy asked.

Those questions seemed to indicate that Kennedy is thinking about this case along mostly the same lines that have previously led him to rule in favor of gay rights.

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But oral arguments are always an imperfect guide to the justices' thinking, and some of the issues that seem most likely to sway Kennedy didn't get a particularly thorough hearing Tuesday.

John Bursch, the attorney who argued on behalf of states' bans on same-sex marriage, was unable to focus his argument time on the part of his case that's most likely to win over Kennedy. He spent most of his time defending the idea that states ban same-sex marriage because they're interested in promoting childbirth and stable family life.

That same rationale—that only opposite-sex couples should be able to marry, because only they can conceive children—also was part of the Court's debate just two years ago over federal marriage restrictions and proved to be a nonstarter with Kennedy. He also wasn't buying it Tuesday.

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"You had some premise that only opposite­-sex couples can have a bonding with the child. That was very interesting, but it's just a wrong premise," Kennedy told Bursch at one point.

If Kennedy is going to rule against same-sex marriage, it's more likely to be on the grounds that the states should be free to make their own decisions. And while that argument was, somewhat surprisingly, on the back burner Tuesday, it still figures prominently in the states' written briefs.

The justices weighed two questions Tuesday: Do states violate the 14th Amendment when they ban same-sex marriage, and do they violate it when they refuse to recognize same-sex marriages legally performed in other states?

There seemed to be a consensus that the Court could not easily split the two questions—meaning that whichever side wins the underlying marriage question almost certainly will also win the recognition question. Kennedy did not engage on the recognition issue.

This article is from the archive of our partner National Journal.

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