To us non lawyers it looks pretty simple: either gay people can legally marry each other or they can't.

But as the Supreme Court prepares to rule on California's Proposition 8, the justices will weigh multiple options. Some decisions would settle the question throughout the country for the foreseeable future. Some could leave it dangling for years to come.

The high court will hear arguments on the case on Tuesday, with a decision expected in June.

To start with, the court isn't just taking on Prop. 8, the California constitutional amendment that banned same-sex marriage. It's also tackling the Defense of Marriage Act, the federal law that denies federal benefits of marriage to  same-sex couples. The court will hear arguments on the DOMA on Wednesday. And the two decisions are intertwined.