It's a frequent question: does appellate oral argument really matter?
We've always harbored the belief that it does in some cases, and if you have any doubts, look no further than today's Ninth Circuit opinion in Nordyke v. King, No. 07-15763 (June 1, 2012), where the en banc court essentially concluded that the issue (whether a county ordinance that makes it a crime to possess a firearm at the County Fairgrounds violates the Second Amendment rights of gun show exhibitors) was moot because the county's attorney at oral argument informed the court that the county now interpreted the ordinance to prohibit only "actual possession" of a gun, and not to bar display of a "properly secured firearm," and that subject to this limitation, gun shows can take place at the fairgrounds. Under that interpretation, the ordinance does not ban guns and is only a reasonable regulation.
Three judges concurred, noting:
Twelve years into this appeal, the County of Alameda now represents that its ordinance presents no barrier to conducting gun shows on its property. Contrary to its previous assertions, the County now concedes that such an event can be held with firearms present and available for meaningful physical inspection by potential buyers.1The County’s sweeping concessions—made at oral argument before the en banc court—change the game and make this a far different case from the one argued before the three-judge panel.-----1. Having made these concessions, the County is bound to them. Should the County at any time fail to apply the ordinance as it represented it at oral argument, Plaintiffs may of course bring suit. Kreisner v. City of San Diego, 1 F.3d 775, 787 n.8, 789 n.10 (9th Cir. 1993). And, of course, if we have misinterpreted the County’s representations, either party may file a petition for rehearing. See Fed. R. App. P. 35.
All this begs the question of why it took "twelve years" of appeals for the County to finally concede that gun shows are indeed allowed on County property, but there you have it.