Proponents of Proposition 8 are trying to subvert the California constitution for a second time, argues the legal team of Ted Olson and David Boies, in a brief filed Monday with the California Supreme Court.

The brief is in preparation for oral arguments in September on the question of whether there is any authority in California law to give Yes on 8 officials standing to represent voters in a federal court case which elected state officials chose not to appeal.

The case is Perry v. Schwarzenegger, in which a U.S. district court judge ruled last August that the 2008 initiative banning recognition of same-sex marriages in California violated the federal constitution. The California governor and attorney general were only passive defendants at the district court level and declined to appeal the district court decision. But Yes on 8 was allowed to defend Proposition 8 in the district court and now seek the right to appeal the decision to the 9th Circuit U.S. Court of Appeals.

A three-judge panel of the 9th Circuit has already heard oral arguments on the merits of the appeal, and it heard arguments concerning whether Yes on 8 has standing to bring the appeal. But before it issues an opinion, the panel has said it would like to hear from the California Supreme Court whether there is any authority in state law to provide Yes on 8 with standing. The panel’s request is essentially following a procedure laid out for it by the U.S. Supreme Court in an earlier, unrelated, voter case.

In its brief, the Olson-Boies team argues that allowing Yes on 8 standing to represent voters after the state’s election officials have decided against appeal would “subvert the express constitutional authority of the Governor and Attorney General to direct the defense of state laws.”

Allowing Yes on 8 to pursue the appeal of a decision that the state’s elected legal officers have chosen not to appeal, said the brief,  “would upend the settled separation of powers and eviscerate the constitutional authority of the Governor and Attorney General….”

“The Governor and Attorney General have decided that the arbitrary, discriminatory, and irrational restriction on the right to marry imposed by Proposition 8 should not be defended on appeal, concludes the brief. “Under California law, that is the end of the matter. Neither proponents—nor any other private party—can usurp the constitutional prerogative of the Governor and Attorney General to decide that, in some circumstances, it is in the best interests of California, and all its citizens, for the State not to participate in the defense of a patently unconstitutional initiative. Proponents’ remedy for their disagreement with their elected officials lies at the ballot box-not in this, or any other, Court.”