The Five Things You Need to Know About the Supreme Court’s Gay-Marriage Case

Justice Anthony Kennedy will probably cast the deciding vote on a closely divided high court

A demonstrator outside the U.S. Supreme Court in Washington, D.C., on March 26, 2013.

Photographer: Andrew Harrer/Bloomberg

The U.S. Supreme Court has agreed—finally—to say whether the Constitution protects gay marriage. Here are answers to the five questions you’re asking:

1. What’s been the holdup?
Actually, the justices are moving with what in their marble-pillared realm constitutes a sprightly step. Yes, the debate about gay marriage has raged for a while. Massachusetts became the first state to recognize same-sex unions 11 years ago. But the issue crystalized at the highest court in the land only in June 2013. That’s when the justices struck down a 1996 statute that banned federal recognition of same-sex marriage. President Bill Clinton, a Democrat, had signed that statute, although he’s since disavowed the position, as has his wife, Hillary, the presumed Democratic front-runner in the 2016 presidential race. It’s important to recall that until recently there’s been a bipartisan consensus in Washington opposing gay-marriage rights. Now the Supreme Court could finish a startling shift by declaring that the constitutional right to “equal protection” requires that homosexuals have the same access as heterosexuals to the civic advantages of matrimony.

2. What prompted the justices to take the case now?
Just last fall, the Supreme Court sidestepped gay marriage when it declined to review cases arising from federal appellate panels in Chicago, Denver, and Richmond, Va. Each of those lower courts had ruled that the Constitution does protect same-sex couples. Then, in November, another panel, this one in Cincinnati, went the other way, declaring that gay couples do not have a fundamental right to wed. That created a conflict among lower courts. Resolving such conflicts is one of the main reasons the Supreme Court agrees to hear cases. On Friday the justices said they’d use disputes involving gay couples from Michigan, Ohio, Kentucky, and Tennessee to announce a nationwide rule.

3. What’s the state of play going into the Supreme Court case?
As a result of lower-court rulings, legislative enactments, and popular votes, homosexual couples can already wed in 36 states and the District of Columbia; 14 states still ban gay marriage. Members of the Supreme Court won’t be debating their personal views on the wisdom of same-sex unions, although such views inevitably color any consideration of morally tinged legal questions. Instead, the justices will rule on whether, in light of the Constitution’s guarantee of equality, states have the authority to deny gays the right to marry.

4. How will the arguments play out?
It’s likely that gay marriage will come down to a 5 to 4 vote, with the “swing justice,” Anthony Kennedy, casting the deciding yea or nay. Keep an eye on two conflicting lines of reasoning: Advocates (and justices) sympathetic to gay marriage will compare it to interracial marriage. Racially mixed couples were banned from marrying in some states as recently as 1967, when the Supreme Court ruled in the poetically named Loving v. Virginia that skin color could not be used as a basis for denying a wedding license. Opponents of gay-marriage rights will counter that the sanctity of “state democratic processes” requires that the federal judiciary allow the marriage debate to play out in the rough-and-tumble of politics. Which argument will appeal more powerfully to Kennedy? That’s the question.

5. When will we know the outcome?
Stay tuned for oral arguments in April and a decision in late June.

Before it's here, it's on the Bloomberg Terminal.