California's same-sex marriage ban endured its latest legal test Tuesday as the state's high court grilled attorneys on whether Proposition 8's backers have legal authority to appeal a federal ruling that overturned the voter-approved measure.

The tenor of the justices' questioning during the more than hour-long hearing often leaned in favor of arguments by backers of the ban, who argue that the state Constitution gives ballot initiative proponents legal authority to defend their measures in court.

On that critical question, several justices noted that the California Supreme Court always has, as a matter of practice if not written policy, allowed the sponsors of ballot questions to appear before it when their measures were challenged.

"Never in any recorded (case) have proponents been denied the right to advance their interests," Associate Justice Kathryn Werdegar noted during the closely watched arguments. "The present state of California law is we allow liberal intervention."

The Supreme Court is examining the scope of the power afforded the official backers of ballot initiatives at the request of a federal appeals court that is reviewing a federal judge's year-old ruling that Proposition 8 violates the constitutional rights of same-sex couples.

The 9th U.S. Circuit Court of Appeals has expressed doubts about the ability of Proposition 8's sponsors to challenge the lower court ruling absent the involvement of California's governor or attorney general, both of whom agreed the ban was unconstitutional and refused to appeal.