Supreme Court Declares Same-Sex Marriage Legal In All 50 States

States cannot keep same-sex couples from marrying and must recognize their unions, the Supreme Court says in a ruling that for months has been the focus of speculation. The ruling was made by a 5-4 decision.

The justices ruled in Obergefell v. Hodges, which is linked to three other cases. Together, they involve a dozen couples who challenged same-sex marriage bans in Ohio, Michigan, Kentucky and Tennessee – the only states whose bans on marriage between gay and lesbian couples had been sustained by a federal appeals court.

Today's ruling overturned that decision by the 6th Circuit Court. As the Supreme Court's summary states, "The history of marriage is one of both continuity and change."

MORE: Indiana Responds To Gay Marriage Ruling 

The justices had been asked to decide whether the Fourteenth Amendment requires states to a) license same-sex marriages and b) recognize such unions that were made in other states.

The Fourteenth Amendment, we'll remind you, was ratified shortly after the Civil War. It has to do with U.S. citizenship – and with providing equal protection for all citizens.

Before Friday's ruling, gay marriage had already been made legal in 37 states – by either legislative or voter action or by federal courts that overturned state' bans.

As NPR's Nina Totenberg reported when the Supreme Court heard the current case back in April, conservative justices had pointed questions for the attorneys:

"Justice Scalia asked whether ministers would be able to refuse to marry two gay men. The answer was that it has to be worked out under state laws. He said, but that could happen — it could happen that a minister would be forced to marry two gay men, in violation of his beliefs.

"Justice Alito asked, well then why not marry four gay men together? Why just two?"

The ruling announced Friday adds new definition to an issue that has remained controversial even as an increasing number of Americans say they support equal marriage rights for same-sex couples. A recent Gallup poll found that 60 percent of Americans – an all-time high – support extending the same rights and privileges to same-sex marriages as traditional ones.

That figure included "37 percent of Republicans, 64 percent of independents, and 76 percent of Democrats," as we reported last month. And it included all age groups except for one: those 65 and over.

The court noted the change in thinking, stating:

"Well into the 20th century, many States condemned same-sex intimacy as immoral, and homosexuality was treated as an illness. Later in the century, cultural and political developments allowed same-sex couples to lead more open and public lives. Extensive public and private dialogue followed, along with shifts in public attitudes. Questions about the legal treatment of gays and lesbians soon reached the courts, where they could be discussed in the formal discourse of the law."

For supporters of same-sex marriage, today's ruling comes as a long-awaited bookend to the Supreme Court's 2013 ruling that struck down the federal Defense of Marriage Act and required the U.S. government to provide the same benefits to both gay and heterosexual couples.

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