All parties have now filed briefs on the question of whether a stay should be granted which would continue Prop 8 in effect until the case is finally decided by an appellate court, possibly the Supreme Court. The two questions relevant to granting a stay are which side is likely to win on the merits at the appeal level and the extent of the likely harm from either granting, or not granting, the stay.
The Prop 8 supporters' Motion for a Stay stressed the harm that would come from the uncertain validity of any marriages occurring during the appeals process. The Plaintiffs' Opposition to a Stay responded to that argument in part by emphasizing that both the Governor and Attorney General support letting marriages proceed. Judge Walker especially cannot ignore the Opposition by the Governor to the Stay Motion.
The Plaintiffs' brief in opposition also added a brand new argument to the mix: that the proponents of Prop 8 don't have standing to appeal. Because neither the Governor nor the AG would defend Prop 8 in this case, the organizations behind the campaign intervened as defendants. Plaintiffs are now making a quite clever argument that this group has no greater standing than any other group of Prop 8 supporters, and thus cannot satisfy the jurisdictional requirements for pursuing an appeal.
So there is nothing to do but wait for Judge Walker's ruling. My hunch is that it will come early next week, but I'm not betting either way on how he will rule. The man is nothing if not unpredictable.
Even if Judge Walker denies the stay, he may postpone the effective date to give the losing side time to race to the Ninth Circuit with an emergency appeal. The side that loses there may seek relief from the Supreme Court, just on the question of the stay. It could be a roller coaster, for at least a few days.
With the support of the Governor and AG, the plaintiffs' lawyers will have to argue that Judge Walker's decision on the merits is so clearly the correct interpretation of the Constitution and the situation for gay couples in California so dire, that stopping enforcement of Prop 8 is urgently needed. If they fail in that effort, it won't set any precedent for how the ultimate appeal will be decided, but it sure would take the shine off the original opinion.
Meanwhile, whatever happens with the stay, Prop 8's supporters have already started the clock running on the appeal of the Walker opinion on the merits. It has been docketed in the Ninth Circuit [No. 10-16696] and a scheduling order entered. Briefs for those defending Prop 8 are due November 12, and briefs for the plaintiffs are due December 13. Based on that schedule, according to the Ninth Circuit web site for average waiting times (and thanks to Jon Davidson for this info), the Court of Appeals is not likely to hear argument for at least a year.