The federal appeals court due to decide if California’s gay marriage ban is unconstitutional has said it can not make a decision until the state’s Supreme Court rules if the sponsors of Proposition 8 have the authority to defend the measure.

A three-judge panel of the 9th US Circuit Court of Appeals have asked the Californian Supreme Court if the backers of the original ballot (proposition 8) can step in to defend the ban as state officials have refused to defend the ban on gay marriage. The Supreme Court does not have to respond, but it is expected to as the federal court says they may have dismiss the case without knowing the answer.

“This court is obligated to ensure that it has jurisdiction over this appeal before proceeding to the important constitutional questions it presents, and we must dismiss the appeal if we lack jurisdiction,” the judges wrote.

“We are now convinced that proponents’ claim to standing depends on proponents’ particularized interests created by state law or their authority under state law to defend the constitutionality of the initiative,” the panel said. “We therefore request clarification in order to determine whether we have jurisdiction to decide this case.”

The confusion stems from a ruling by Judge Vaughn Walker in August, which ruled that the ban on gay marriage in California was wrong. The decision came after a lengthy “trial” of the arguments for and against allowing gay couples to marry. “The evidence presented at trial and the position of the representatives of the State of California show that an injunction against enforcement of Proposition 8 is in the public’s interest,” Judge Walker wrote at the time.

“Accordingly, the court concludes that the public interest counsels against entry of the stay proponents seek.”

Unusually, the official ‘defendants’ of that appeal, then governor Arnold Schwarzenegger and Attorney-General Jerry Brown, refused to defend the ban. So, the groups who supported the introduction of Prop 8 have been arguing that they have the right to defend the ban on marriage.

Lawyers for the gay couples who begun the case have argued that Judge Walker’s decision is binding only in the state of California. If this argument is accepted, then the case will not have to pass onto the federal Supreme Court, something that would delay the introduction of gay marriage by many years.

California legalised marriage for gay couples in 2008 after couples took the state to court over the ban on gays marrying. However, a voter initiative Proposition 8 struck it down in the same year.