On Dec. 6, 2010, a federal appeals court in San Francisco will hear arguments in a case challenging the constitutionality of Proposition 8, a voter-approved 2008 California ballot initiative that banned same-sex marriage in the state. The 9th U.S. Circuit Court of Appeals agreed to hear the case, Perry v. Schwarzenegger, after Proposition 8 was declared unconstitutional earlier in 2010 by a lower federal district court.

The battle over same-sex marriage in California has been long and hard-fought by both sides. The issue came to a head in May 2008, when the state’s Supreme Court declared an earlier law banning same-sex marriage to be in violation of the California Constitution. That decision, which legalized gay marriage in the state, prompted opponents to put a voter initiative on the ballot that would amend the state constitution to limit marriage to the union of a man and a woman. In November 2008, that initiative, Proposition 8, was narrowly approved by voters, and same-sex marriage was once again illegal in California.

After an unsuccessful appeal to the state’s Supreme Court, Proposition 8 opponents filed suit in federal district court, arguing that the proposition violated the Equal Protection and Due Process clauses of the U.S. Constitution. The lower federal court agreed with this argument and declared Proposition 8 to be unconstitutional. The case now moves to the 9th Circuit, which will likely issue a ruling in early 2011. Regardless of the appeals court’s decision, the case is very likely to be appealed to the U.S. Supreme Court.

The Pew Forum has many resources relevant to this case, including:

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