The California Supreme Court has handed what appears to be the final legal defeat to the group behind Proposition 8 and its efforts to halt same-sex marriages in the stage.

The court met in closed session and rejected the arguments of ProtectMarriage that a single judge did not have the authority to overturn a statewide law.

That judge was Chief U.S. District Judge Vaughn R. Walker who in 2010 declared California’s ban on gay marriage, passed by voters in 2008, to be unconstitutional.

Proposition 8 was struck down in June when the US Supreme Court allowed Vaughn’s ruling to stand. It ruled that ProtectMarriage did not have the right to defend Proposition 8 in federal court.

Two days after the 26 June decision, an appeals court in San Francisco lifted its hold on Vaughn’s decision and state officials ordered gay marriages to resume.

California voters may have approved Proposition 8 nearly five years ago but many appear to have changed their mind on gay marriage since then.

A poll in May done by the nonpartisan Public Policy Institute of California showed that 56% of Californians now favor gay marriage – the highest level of support ever shown in the state.

The numbers were almost a complete reversal of a 2000 poll when 55% of respondents were against gay marriage. Since then, support had steadily climbed reaching 50% in March 2010 and 53% in January.