SAN FRANCISCO (AP) — A federal appeals court says it can’t decide if California’s gay marriage ban is constitutional until the state’s highest court weighs in on whether Proposition 8′s sponsors have the authority to defend the ban.

In a brief order filed Tuesday, a three-judge panel of the 9th U.S. Circuit Court of Appeals asked the California Supreme Court to decide if the backers of ballot propositions can step in to defend voter-approved measures in court when state officials refuse to do so.

Dean Erwin Chemerinksy of the U.C. Irvine School of Law says the issue of legal standing is central to the ongoing court battle.

The question is central to the future of Proposition 8 because former Gov. Arnold Schwarzenegger and then-Attorney General Jerry Brown refused to appeal a San Francisco trial judge’s August decision striking down the ban as a violation of gay Californians’ civil rights.

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