Might judge’s discovery overturn decades of ATF interpretation on what constitutes a “receiver”?

In a startling California case, the federal government dropped charges against someone who had been manufacturing and selling guns without a manufacturer’s license. The news article claims that the federal government dropped the case because they were worried that the decision would create a precedent. But it isn’t obvious that should matter because once other lawyers know that the existing law doesn’t cover cases that the ATF has used it to cover, they damage is already done.

From a Fox TV station in North Carolina:

The guns are sometimes assembled from separately acquired parts. Under federal law, the one regulated individual part of a firearm is what’s known as the frame or receiver — a piece that, among other things, provides a housing for the hammer and firing mechanism of a gun.

Though incapable of firing a round, the part is considered a gun in its own right and is subject to the same restrictions as a fully intact firearm. Manufacturers must stamp it with a serial number and licensed dealers are required to conduct background checks on prospective buyers. The restrictions are intended, in part, to keep felons and other people prohibited from possessing firearms from acquiring them piece by piece.

AR-15s, however, do not have a single receiver that meets that definition. They have both an upper and lower receiver — two parts as opposed to the single part described in the law.

At issue in Roh’s case was whether the law could fairly be interpreted to apply to just the lower receiver of the AR-15, as the ATF has been doing for decades. . . .