The Rule of Law and constitutional separation of powers matter, said the Supreme Court in Friday’s 6-3 ruling in Garland v. Cargill. In striking down the bump stock ban issued by the Bureau of Alcohol, Tobacco, Firearms and Explosives in 2017, the Court said the case was less about the Second Amendment than it was a rebuke of executive overreach.

“On more than 10 separate occasions,” noted Supreme Court Justice Clarence Thomas in his majority opinion, the ATF declined to regulate bump stocks because they do not qualify as machine guns under the National Firearms Act of 1934. That law all but banned “machineguns” and was later upheld by the Supreme Court in United States v. Miller (1939). The law defined a “machinegun” as “any weapon which shoots, is designed to shoot, or can be readily restored to shoot, automatically more than one shot, without manual reloading, by a single function of the trigger” (26 U.S.C. §5845(b) [emphasis added]).

Thus, Thomas took space in his ruling to explain the basic functionality of a bump stock: A machine gun “automatically” fires multiple rounds “by a single function of the trigger,” he said, but bump stocks don’t do that. They are instead “a plastic casing that allows every other part of the rifle to slide back and forth.” That helps fire rounds more quickly, but it is not, based on the statutory language, a machine gun. That definition, Thomas said, “hinges on how many shots discharge when the shooter engages the trigger.” A rifle with a bump stock is still a semiautomatic weapon — one bullet per trigger pull.

The ATF issued the ban under Donald Trump after the Las Vegas massacre, in which the killer used rifles affixed with bump stocks to murder 58 people and wound more than 500. The political pressure to “do something” was immense, and as is often the case these days, it’s easier to let bureaucrats make those decisions than for members of Congress to make tough votes.

Congress abdicating its authority does not confer it on the ATF, no matter how much Democrats hilariously caterwaul about the Supreme Court “legislating from the bench.” No, the Court prohibited the ATF from legislating in Congress’s stead.

There are more than half a million bump stocks in circulation, bought legally by American citizens before the ban. Turning law-abiding citizens into felons with the stroke of a bureaucratic pen is not consistent with the Rule of Law — or even the “democracy” that left-wingers are so hot and bothered about protecting.

Justice Sonia Sotomayor was caught up in the emotion of it all, as well. In her dissent, she even tried to argue with Thomas on the technicality of function. “Just as the shooter of an M16 need only pull the trigger and maintain backward pressure (on the trigger),” she wrote, “a shooter of a bump-stock-equipped AR-15 need only pull the trigger and maintain forward pressure (on the gun).” That’s simply incorrect.

Amusingly, Sotomayor scored what in soccer is known as an own goal, writing, “Within a matter of minutes, using several hundred rounds of ammunition, the [Las Vegas] shooter killed 58 people and wounded over 500. He did so by affixing bump stocks to commonly available, semiautomatic rifles.”

Did you catch that? “Commonly available.” In its 2008 Heller ruling, the Supreme Court determined that the Second Amendment, at the very least, protects firearms “in common use.” Sotomayor just admitted — in a Supreme Court dissent on firearms law — that AR-15s are in common use.

Second Amendment advocate Charles C.W. Cooke writes, “Sotomayor even uses the word ‘common’! Not ‘everyday’ or ‘universal’ or ‘normal’ or ‘usual,’ but common — the very word that was used in Heller.”

She’s right, of course, and that goes a long way to undermining Joe Biden’s commonly used refrain demanding a renewed ban on such firearms. He often demands a ban, by the way, in conjunction with threatening the American people with F-15s and sometimes even nuclear weapons. Both are more lethal than bump stocks.

Sotomayor was wrong, however, to write, “When I see a bird that walks like a duck, swims like a duck, and quacks like a duck, I call that bird a duck.” If the law says it’s a bird, it’s a bird.

Again, the point of this ruling is primarily about the constitutional separation of powers, which Justice Samuel Alito made plain in his concurrence. “There is a simple remedy for the disparate treatment of bump stocks and machineguns,” he says. “Congress can amend the law — and perhaps would have done so already if ATF had stuck with its earlier interpretation. Now that the situation is clear, Congress can act.”

This ruling will no doubt have an effect on other ATF cases. The bureau already lost a pistol brace case before a district court last week, as well as a case dealing with the definition of a gun dealer back in April.

In short, the ATF is not empowered to enact the Left’s gun-grabbing agenda without legislation passed by our elected representatives. And even then, the government is bound by the Second Amendment. Memo to Joe Biden and other presidents: Governing by executive diktat is no way to preserve “democracy.”

Follow Nate Jackson on X/Twitter.