A federal appeals court Tuesday struck down California's Proposition 8, handing gay groups a big win while avoiding the larger question of whether the U.S. Constitution guarantees gays nationwide the right to "marry."

The outcome by the Ninth Circuit Court of Appeals was not a huge surprise, as the three-judge panel seemed inclined during oral arguments to overturn Prop 8, which defines marriage as between one man and one woman and was passed at the ballot in 2008. But it was a landmark decision and marked the first time an appeals court in the U.S. has ruled that same-sex couples in a state have a right to "marry." The ruling will be appealed and could end up before the U.S. Supreme Court.