For years, the Justice Department’s Bureau of Alcohol, Tobacco, and Firearms has maintained that “bump stocks”—devices that allow a firearm to reciprocate slightly and assist in “bump firing”—are not “machineguns.” From 2007 to 2017, spanning multiple administrations (including the current one), the ATF issued 10 different opinion letters confirming that the devices were not “machineguns” or “machine gun conversions,” and thus did not fall under the purview of the National Firearms Act of 1934 and Gun Control Act of 1968, two federal laws which heavily regulate machine gun ownership.

Under federal law, a “machinegun” is a device “which shoots … automatically more than one shot … by a single function of the trigger.” With language so clear, the provision was never considered ambiguous by a reviewing court over 80 years of decisions—and the ATF’s interpretation remained consistent. It is for this reason that bump stocks, and crank-operated “Gatling guns,” while having a high rate of fire, have never been considered “machineguns.” (Yes, virtually anyone can own a Gatling gun under federal law.) What could change the state of such settled law, then? Political expediency.

After the October 2017 mass shooting in Las Vegas, where the shooter used a bump stock, President Trump made clear that he intended to see the devices banned “without going through Congress.” The administration then announced that it intended to “clarify” the NFA and GCA to include bump stocks within the statutory definition of “machinegun.” The issue is, of course, that no amount of “clarification” can lawfully make a statute say something it does not. That, however, did not seem to deter the ATF when it published a Notice of Proposed Rulemaking in March, threatening to stretch statutory language beyond the point of tearing, all in an attempt to use an 83-year-old law to do away with bump stocks.

Our Constitution requires that new laws be brought through Congress, not shoehorned into old ones by executive agencies. In that light, we have filed a regulatory comment, expressing our view that the ATF’s new “interpretation” is an attempt to force new restrictions as a matter of political expediency, not a good faith interpretation of existing law. The president undoubtedly has the authority to direct the actions of his principal officers, but when those directions urge the reversal of longstanding previous interpretations based on an unambiguous statute, they smell more of an attempt to improperly change the law than a valid exercise of constitutional authority.