The Supreme Court is expected to rule Wednesday in a pair of historic cases on same-sex marriage.
Most court observers expect the court to rule narrowly, putting its stamp of approval on the legal recognition of same-sex marriage while leaving it mostly to the states to actually expand same-sex couples' rights.
But those expectations are hardly a guarantee, as the court proved a year ago with its ruling upholding President Obama's healthcare law.
The rulings on same-sex marriage cap off a term — and a week — that will loom large in Chief Justice John Roberts's legacy on civil rights issues.
It would be difficult for the justices to ignore the dramatic shift in public opinion as they rule on marriage rights. Legal observers say the justices and Roberts in particular would surely want to avoid coming down on the "wrong side of history" by ruling against same-sex marriage rights.
Yet during oral arguments in the marriage cases, several of the justices seemed to be searching for ways to avoid a broad ruling declaring a constitutional right to marriage equality in every state.
The court is set to rule in two cases on same-sex marriage. The first challenges the Defense of Marriage Act (DOMA) — the federal law, enacted in 1996, that prohibits same-sex couples from receiving federal benefits, even if they live in a state where same-sex marriage is legal.
Most observers expect the court to strike down DOMA, but as an encroachment on the rights of states rather than those of same-sex couples.
The challenge to DOMA was filed by Edith Windsor, a New York widow who inherited her late wife's home but was forced to pay dramatically higher property taxes than she would have if she had married a man, even though the state recognized her marriage.
The second and more complicated case is a challenge to California's Proposition 8, which banned same-sex marriage in the state.
The court has five basic options in the Proposition 8 case. It could uphold the state's ban on same-sex marriage, or decline to rule based on procedural issues.
That leaves three ways to strike down the same-sex marriage ban. The most sweeping option would be to declare that the Constitution guarantees all couples the right to marry, which would make same-sex marriage legal immediately in all 50 states.
Many gay-rights activists, including some libertarian lawyers, want the court to go that far. But Justice Anthony Kennedy, who will almost surely cast the deciding vote, did not seem inclined during oral arguments to rule so broadly.
One option for a narrower ruling would strike down Proposition 8 on the grounds that California has extended all of the legal rights of marriage to same-sex couples except for the word itself.
That avenue, endorsed by the Obama administration, would make same-sex marriage legal in about eight states.
Finally, the court could strike down Proposition 8 in a way that only applies to California. Such a decision would signal that the court is fundamentally on the side of marriage equality, but would leave the states to work toward equality largely at their own pace.