The U.S. Supreme Court will confront two distinct same-sex marriage cases and can choose from a wide array of outcomes in ruling on California's Proposition 8 ban on same-sex marriage and the federal Defense of Marriage Act. Here's a look at potential outcomes.

Q What are the cases?

A On Tuesday, the court has scheduled 60 minutes of argument in Hollings­worth vs. Perry. This involves a challenge to California's Proposition 8, a state constitutional amendment prohibiting same-sex marriages that voters adopted in 2008. On Wednesday, the court has scheduled an unusually long 110 minutes of argument in U.S. vs. Windsor, which challenges DOMA, a 1996 law that prohibits federal benefits from going to same-sex married couples.

Q: What if the court upholds Prop 8?

A: This would leave gay Californians without the right to marry in the state and would tell the roughly 40 states that do not allow same-sex marriages that there is no constitutional problem in limiting marriage to a man and a woman.

Q: What if it strikes down Prop 8?

A: A ruling in favor of the two same-sex couples who sued to invalidate the voter-approved gay marriage ban could produce one of three possibilities.

Nationwide: The broadest would apply across the country, in effect invalidating constitutional provisions or statutes against gay marriage everywhere.

"Nine-state solution": Or a majority of the justices could agree on a middle option that applies only to California as well as Colorado, Delaware, Hawaii, Illinois, Nevada, New Jersey, Oregon, and Rhode Island. Those states already treat gay and straight couples the same in almost every respect through civil unions or domestic partnerships. This would say that the Constitution forbids states to withhold marriage from same-sex couples while giving them all the basic rights of married people. But this ruling would leave open the question of whether states could deprive gay couples of any rights at all.

California only: The narrowest of these potential outcomes would apply to California only. The justices essentially would adopt the rationale of the federal appeals court that found that California could not take away the right to marry that had been granted by the state Supreme Court in 2008 before Proposition 8 passed later that year.

Q: Are there other potential outcomes?

A: Yes, the court has a technical way out of the case without deciding anything about same-sex marriage. The Proposition 8 challengers argue that the private parties defending the provision — members of the group that helped put the ban on the ballot — did not have the right to appeal the trial judge's initial decision striking it down or that of the federal appeals court.

The justices sometimes attach great importance to this concept, known as standing. If they find Proposition 8's proponents lack standing, the justices also would find the Supreme Court has no basis on which to decide the case.

Q: Are the possibilities for the DOMA case as complicated?

A: No, although there are some technical issues that could get in the way of a significant ruling.

Q: What happens if the court upholds Section 3 of DOMA, defining marriage as the union of a man and a woman?

A: Upholding DOMA would not affect state laws but would keep in place federal statutes and rules that prevent legally married gay Americans from receiving a range of benefits that are available to married people. These benefits include breaks on estate taxes, health insurance for spouses of federal workers and Social Security survivor benefits.

Q: What if it strikes down DOMA?

A: That would allow legally married gay couples, or in some cases, a surviving spouse in a same-sex marriage, to receive benefits and tax breaks resulting from more than 1,000 federal statutes in which marital status is relevant. For Edith Windsor, 83, a New York widow whose case is before the court, such a ruling would give her a refund of $363,000 in estate taxes that were paid after the death of her wife, Thea Spyer.

Q: What are the procedural problems?

A: There are questions about whether House Republicans have the right to defend the law because the Obama administration decided not to. If the court finds that it does not have the authority to hear the case, Windsor probably would get her refund because she won in the lower courts, but there would be no definitive decision and DOMA would remain on the books.

associated press