On Thursday, a three-judge panel vacated a ruling by a Maryland district court that had upheld the state’s ban on so-called “assault weapons” and large-capacity magazines (holding more than 10 rounds).

In Kolbe v. Hogan, the panel (in a 2-1 decision) sent the case back to the district court, holding that the district court judge had used the wrong standard to review the law. The district court had rejected the plaintiffs’ Second Amendment claims, concluding that the Maryland restrictions passed constitutional muster under “intermediate scrutiny” review.

However, the Fourth Circuit, in a decision written by Chief Judge William B. Traxler, a Clinton appointee, held that the Maryland law “implicates the core protection of the Second Amendment—‘the right of law-abiding responsible citizens to use arms in defense of hearth and home.’” Traxler wrote that the court was “compelled” by the Supreme Court’s two major prior cases on the Second Amendment, District of Columbia v. Heller (2008), and McDonald v. City of Chicago (2010), “as well as our own precedent in the wake of these decisions, to conclude that the burden is substantial and strict scrutiny is the applicable standard of review.” The Heller and McDonald cases had knocked out the virtual ban on guns imposed by the cities of Washington and Chicago, respectively.

What was most interesting about the decision was the commonsense way in which the Fourth Circuit described the Maryland law on assault weapons and large-capacity magazines (emphasis added):

In April 2013, Maryland passed the Firearm Safety Act, which among other things, bans law-abiding citizens, with the exception of retired law enforcement officers, from possessing the vast majority of semi-automatic rifles commonly kept by several million American citizens for defending their families and homes and other lawful purposes.

The court also pointed out that “the record in this case shows unequivocally” that large-capacity magazines, or LCMs, “are commonly kept by American citizens, as there are more than 75 million such magazines in circulation in the United States.” “In fact,” according to the court, “these magazines are so common that they are standard.”

The court totally rejected the far-fetched argument of the state of Maryland that the Second Amendment does not apply to “detachable magazines because magazines are not firearms—that is, detachable magazines do not constitute ‘bearable’ arms that are expressly protected by the Second Amendment.”

Under that logic, “the government can circumvent Heller … simply by prohibiting possession of individual components of a handgun, such as the firing pin.” But obviously, “without the ability to actually fire a gun, citizens cannot effectively exercise the right to bear arms.” Thus, the right to bear arms applies to all of the “component parts necessary to make the firearms operable,” and that “applies to the magazines in question.”

Robert B. King, also a Clinton appointee, dissented. He argued that there is “no sound reason to conclude that the Second Amendment affords” any protection “whatsoever” to semi-automatic rifles or LCMs, and that strict scrutiny should not apply, even though a violation of a core constitutional right is being claimed.

The Fourth Circuit did uphold the district court’s dismissal of the plaintiffs’ claim that allowing retired law enforcement officials to own such semi-automatic rifles when ordinary citizens were banned from owning them was a violation of the Equal Protection Clause.

The case is obviously not over. But it is still a good result and a strike against Maryland’s overly restrictive gun law.