The Supreme Court agreed Friday to definitively answer whether the Constitution allows states to ban same-sex marriage, plunging the court directly into one of the nation's biggest legal and cultural issues.
By agreeing now to take up the question, the court allowed time for the case to be decided by the end of the current term in late June. The case will be argued in late April.
"It's impossible to overstate the historic significance of a decision on such a fundamental piece of our social fabric," said Tom Goldstein, a Washington lawyer who argues frequently before the Supreme Court.
The court granted cases from Kentucky, Michigan, Ohio and Tennessee. It said it would decide whether states can refuse to issue same sex-marriage licenses and whether they can refuse to recognize same-sex marriages legally performed elsewhere.
The issue comes to the justices after a tidal wave of lower court rulings struck down marriage bans in one state after another — nearly 60 separate decisions in more than half the states over the past 18 months.
Thirty-six states now permit gay people to get married, covering roughly 70 percent of the U.S. population. Court decisions on hold have struck down bans in five other states.
The surge of lower court rulings quickly followed the Supreme Court's 2013 decision that struck down a law barring the federal government from recognizing same-sex marriages in states where they're legal.
But courts have upheld bans on marriage for gay couples in four other states — Kentucky, Michigan, Ohio and Tennessee — a split the Supreme Court will now resolve.
Public opinion has shifted in recent years. The first Gallup poll on the subject showed only 27 percent approval for same-sex marriage in 1996. Gallup's most recent poll, taken last year, showed 55 percent approval.