Prop 8 bans same-sex marriage in California; it was approved by voters in 2008 by 52 percent of the vote. It was struck down by a federal judge and if the Supreme Court upholds that decision, same-sex marriage could begin again in California. Justices could also use the case to legalize same-sex marriage across the country.
The High Court could also issue a ruling on the federal Defense of Marriage Act. It's a federal law that defines marriage as being only between a man and a woman. The law prevents married gay couples from receiving a number of federal benefits.
Last night a Pride kick-off event was held in San Francisco which honored 400 movers and shakers of the LGBT community. The Supreme Court and Prop 8 were on the minds of many at the event.
"I feel very hopeful about it. I'm really excited and I think what we see around the country -- so many states have marriage equality movements. So this is a very exciting time and for it to happen in the middle of Pride, I think couldn't be any sweeter," said former San Francisco Supervisor Bevan Dufty.
The Supreme Court rulings could come next week.