LOS ANGELES (RNS) The California Supreme Court handed conservatives a big victory on Thursday (Nov. 17) by allowing them to defend a statewide ban on gay marriage that a federal judge struck down as unconstitutional last year.

The court’s 7-0 ruling is a victory for conservative and evangelical backers of Proposition 8, the 2008 ballot initiative that ended same-sex marriage in California. State officials have declined to defend the measure in a federal appeals court.

“When an initiative measure is challenged in court, the integrity and effectiveness of the judicial process require that a competent and spirited defense be presented,” Justice Joyce Kennard wrote in a concurring opinion.

“If public officials refuse to provide that defense, the ability of the initiative proponents to intervene in the pending litigation, and to appeal an adverse judgment, is inherent in, and essential to the effective exercise of, the constitutional initiative power.”

Prop 8 supporters have been working on the case with the Alliance Defense Fund, a leading Christian law firm. Mormon and Roman Catholic churches also lent strong support to the proposition though the various court challenges.

Andrew Pugno, an attorney for ProtectMarriage.com, told a San Francisco radio station that the state court’s ruling “really is a huge disaster for the homosexual marriage extremists.”

Attorney Kate Kendell of the San Francisco-based National Center for Lesbian Rights said only state officials should be able to defend the initiative in court, even if they chose not to.

“We disagree profoundly … that a handful of unelected initiative sponsors have the power to represent the interests of the entire public and to override the decisions of the state’s elected executive officers,” she said.