Last year, a three-judge panel at the Ninth Circuit Court of Appeals issued one of the most resounding pro-Second Amendment decisions in recent memory:

In a ruling Thursday afternoon, the 9th Circuit Court of Appeals reversed an earlier court ruling that self-defense was not a good enough reason for granting a CCW in California, stating that the Second Amendment guarantees the right to carry a gun in public.
This is seen as a strike at the practice of ‘may-issue’ in California, which is where a citizen has to prove why he or she needs a permit and if they do so effectively, the local authorities ‘may issue’ one. This is different from ‘shall-issue’ states where most lawful citizens can simply apply for and be granted a permit after a background check and fees.
According to Handgunlaw.us, just eight states, including California, are currently considered may-issue states, with the majority being shall-issue.

Yesterday, the Ninth Circuit announced its intention to rehear that case en banc. Per the Firearms Policy Coalition:

In orders released moments ago, the Ninth Circuit Court of Appeals has ordered en banc rehearings in the landmark right-to-carry cases Peruta v. San Diego and Richards v. Yolo County Sheriff Ed Prieto.

As David Hardy of Arms and the Law notes today, the questions at play in those cases will be examined by “a panel of ten randomly-chosen judges (out of around 28 active duty ones) plus the chief judge.” Whatever they decide, the consequences of their decision will likely be felt outside of California and Hawaii (the Ninth covers many more states, but those are the only two that do not have “shall issue” in place). Why? Well, because at present there is a pronounced circuit split on the question of “good cause” requirements. Indeed, as Dave Kopel observed at the time that Peruta was initially decided:

Today’s decision creates a split of the Seventh and Ninth Circuits vs. the Second, Third, and Fourth Circuits. The Peruta Court says that Circuits 2-4 erred by relying on cases which are, pursuant to Heller, incorrect, because those cases say that the only purpose of the Second Amendment is for the militia; Heller teaches that the Second Amendment right includes personal self-defense, and need not be connected to militia service.

If the Ninth Circuit does vacate Peruta, this split will become less acute, and the chances of the Supreme Court’s electing to take up the matter will be diminished. That’s bad news for anyone living in a jurisdiction that does not recognize their right to carry.