The ruling will not take effect immediately because the court gives the losing side roughly three weeks to ask for reconsideration.
The Supreme Court ruled Friday that same-sex couples have a right to marry nationwide, in a historic decision that invalidates gay marriage bans in more than a dozen states.
Gay and lesbian couples already can marry in 36 states and the District of Columbia. But in a 5-4 ruling, the court held that the 14th Amendment requires states to issue marriage licenses for same-sex couples and to recognize such marriages performed in other states.
The ruling means the remaining 14 states that did not allow such unions, in the South and Midwest, will have to stop enforcing their bans.
Justice Anthony Kennedy wrote the majority opinion, just as he did in the court’s previous three major gay rights cases dating back to 1996.
“No union is more profound than marriage,” Kennedy wrote, joined by the court’s four more liberal justices. He continued: “Under the Constitution, same-sex couples seek in marriage the same legal treatment as opposite-sex couples, and it would disparage their choices and diminish their personhood to deny them this right.”