CRS Report – Federal Firearms Law: Selected Developments in the Executive, Legislative, and Judicial Branches. November 3, 2021 [42 pages]: “Firearm regulation in the United States is an area of shared authority between the federal, state,and local governments. At the federal level, firearm commerce, possession, and transfers are governed largely by two statutory regimes: the National Firearms Act of 1934 (NFA) and the Gun Control Act of 1968 (GCA). The NFA imposes stringent taxation and registration requirements for a specific set of statutorily defined “firearms” deemed to be especially dangerous, such as machine guns and short-barreled rifles. The GCA, which is more broadly applicable to most kinds of commonly available firearms, regulates the manufacture, transfer, and possession of firearms in multiple ways. Among other things, the GCA prohibits certain categories of persons from possessing or receiving firearms and requires individuals or entities “engaged in the business” of manufacturing or selling firearms to be federally licensed (referred to as FFLs). The GCA also obligates FFLs that manufacture firearms to identify each one by means of a serial number and requires FFLs that transfer firearms to conduct background checks on each prospective transferee. Current federal law does not require unlicensed persons who wish to make or assemble a firearm for personal use to stamp it with an identifying serial number, nor must such persons who wish to transfer a firearm from a personal collection or as a hobby conduct a background check on the person to whom the firearm is to be transferred.Recent developments in all three branches of government could affect how these and other provisions of the NFA and GCA are interpreted and applied. In the executive branch, the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), an agency within the U.S. Department of Justice (DOJ),has issued a proposed rule that would clarify when some larger pistols equipped with stabilizing or arm braces are considered short-barreled rifles subject to NFA requirements. Additionally, in an effort to mitigate the availability of so-called “ghost guns”—i.e., firearms that are not identifiable by means of a serial number or other information stamped on the firearm and that are thus more difficult to trace when used in crime—a second ATF proposed rule would, in part, amend regulatory definitions of the term “frame or receiver” (the principal firearm component to which a serial number is affixed) to require serial numbers for certain firearm component kits and incomplete frames and receivers. Beyond these two proposed rules, DOJ also recently published a model “red flag” law—essentially, a provision permitting a court to issue a temporary order barring a person at risk of gun violence from possessing a firearm—that states seeking to establish such laws may use as guidance…”