A federal appeals court in San Francisco announced Monday that it will issue a ruling Tuesday on whether Proposition 8, California's voter-approved ban on same-sex marriage, is constitutional.
A three-judge panel of the 9th U.S. Circuit Court of Appeals will decide whether to uphold a ruling in which now-retired U.S. District Judge Vaughn Walker of San Francisco struck down the measure.
Walker, acting on a lawsuit filed by two same-sex couples, ruled in August 2010 that the marriage ban violated the U.S. Constitution's guarantees of equal protection and due process.
That decision is being appealed by sponsors of the 2008 ballot measure and their campaign committee, Protect Marriage.
Proposition 8's sponsors argue that voters who approved it were entitled to believe that restricting marriage to heterosexuals would promote responsible child-rearing by married biological parents.
Same-sex marriage advocates say that allowing gay marriage wouldn't hurt heterosexual unions and would help the thousands of California children who are being raised by gay and lesbian parents.
Tuesday's decision will not be the last stop in the case. The three-judge panel's ruling can be appealed to an expanded 11-judge panel of the appeals court and then to the U.S. Supreme Court.
The appeals court will also rule Tuesday on a second issue of whether Walker should have stepped down from hearing the case because he is gay and is in a long-term relationship.
The Protect Marriage sponsors contend Walker had a conflict of interest because he may have wanted to marry.
The plaintiffs in the case argued that judges who are members of a minority group don't need to disqualify themselves from ruling on cases affecting that group.
Another federal trial judge, U.S. District Judge James Ware, agreed last year that Walker did not need to excuse himself from hearing the case. The Proposition 8 sponsors are appealing that decision.