Jeff Chiu / AP Kris Perry, foreground left, kisses Sandy Stier as they are married at City Hall in San Francisco on June 28.

The people behind California's Proposition 8 have launched a new legal effort to stop the state from permitting same-sex marriages.

It's a long shot, but it gets at an issue that has been lurking in the legal dispute all along. The question is whether they've gone to the right place to get it resolved.

The backers of Prop. 8, which amended the state Constitution to ban gay marriage, argue that when the smoke cleared after the U.S. Supreme Court shot down their appeal in late June, what was left was a victory only for the two gay couples who originally challenged the initiative in court. Now that those original plaintiffs are married, they argue, the state is free -- in fact, required -- to go right on enforcing Prop. 8's ban on any further same-sex marriages.

Their reasoning: When the U.S. Supreme Court booted the case, it left intact a 2010 ruling by U.S. District Judge Vaughn Walker that found Prop. 8 unconstitutional. Walker issued an order -- directed to California's governor, attorney general and state officials who oversee county clerks -- barring them "and all persons under their control or supervision" from enforcing Prop. 8.

But Walker, the Prop. 8 proponents argue, lacked legal authority to order state officials to do anything except allow the four gay plaintiffs to get married. And even if he did have that authority, they say, county clerks are not under anyone's supervision when it comes to issuing marriage licenses because the California Legislature gave clerks -- and clerks alone -- the authority to issue them.

"They've got the right issue, but they've gone to the wrong court" said Professor Stephen Vladeck of the Washington College of Law at American University in Washington, D.C., an expert on federal court procedure. "You can't challenge a federal court order in state court."

Late Friday, Attorney General Kamala D. Harris' office said that Harris had filed a brief with the California Supreme Court urging that it deny the proponents' request to stop counties from issuing marriage licenses to same-sex couples.

"Today's filing by the proponents of Proposition 8 is yet another attempt to deny same-sex couples their constitutionally protected civil rights. It is baseless and we will continue to fight against it," Harris said in the statement.

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