In February, a three-judge Ninth Circuit panel held (in Peruta v. County of San Diego (9th Cir. Feb. 3, 2014)) that the Second Amendment secures a right to carry guns in many public places, and not just to possess guns at home. Naturally, this has been quite controversial, but the San Diego County defendants decided not to ask the Ninth Circuit to rehear the case en banc (i.e., by an 11-judge panel). Today, the original panel refused to allow California, the Brady Campaign, and a couple of other groups to intervene in the case in order to petition for rehearing. My understanding is that, in principle, the would-be intervenors could try to get the court to rehear en banc this denial of the petition to intervene — but it’s not very likely.
As a practical matter, though, this decision probably doesn’t mean much, because the same issue has been raised in Baker v. Kealoha, which challenges Honolulu’s restrictive licensing scheme, and in Richards v. Prieto, which challenges the Yolo County (California) scheme. The panel held in plaintiffs’ favor in those cases, citing Peruta, and those defendants did file en banc rehearing petitions. So the Ninth Circuit will now consider those petitions. Stay tuned for what the Ninth Circuit does.