What this charge actually says
The statute opens with a flat ban: "It shall be unlawful for any person" to do any of twelve listed things. Those twelve prohibited acts, lettered (a) through (l), cover the whole life cycle of a regulated weapon. Engaging in the firearms business without paying the occupational tax or registering. Receiving or possessing a weapon transferred or made in violation of the rules. Transferring one. Making one. Obliterating or altering a serial number, or possessing a weapon whose serial number was obliterated. Possessing a weapon with no serial number at all. Moving an unregistered weapon in interstate commerce. Receiving or possessing a weapon that was imported or brought into the United States illegally. And making a false entry on a required application or record.
In practice, one of the twelve does most of the work. Subsection (d) makes it unlawful "to receive or possess a firearm which is not registered to him in the National Firearms Registration and Transfer Record." That is the charge behind most NFA possession cases: the weapon is on the regulated list, and the federal registry does not show it registered to the person holding it. For the big picture of how these cases fit with other gun charges, start with the Federal Firearms Charges hub.
Two things about subsection (d) surprise most readers. First, the word "firearm" here does not mean what it means in ordinary speech. It means only the eight categories defined in section 5845(a), described below. An ordinary hunting rifle or handgun is not an NFA firearm no matter how it was bought. Second, the question is registration to you, the possessor, in one specific federal record. Registration to someone else, a bill of sale, or compliance with state law does not satisfy it.
Which weapons the law covers under § 5845(a)
Section 5845(a) lists eight categories, and only these eight can support an NFA charge:
Short-barreled shotguns: "a shotgun having a barrel or barrels of less than 18 inches in length." Weapons made from a shotgun count too if the modified weapon is under 26 inches overall or has a barrel under 18 inches.
Short-barreled rifles: "a rifle having a barrel or barrels of less than 16 inches in length," again including weapons made from a rifle that end up under 26 inches overall or with a barrel under 16 inches.
Any other weapon: concealable weapons such as smooth-bore pistols built to fire shotgun shells, with exceptions for ordinary rifled pistols and revolvers and for weapons meant to be fired from the shoulder.
Machineguns: "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." The definition also reaches frames, receivers, and parts designed to convert a weapon into a machinegun.
Silencers: any silencer as defined in the general federal firearms definitions.
Destructive devices: bombs, grenades, rockets and missiles above stated propellant and explosive weights, mines, similar devices, and large-bore weapons above one-half inch except shotguns recognized as suited to sporting use.
That list has boundaries, and the boundaries are defenses. The statute says the term "shall not include an antique firearm," and it separately excludes collector pieces the Secretary has found are primarily collector items not likely to be used as weapons. The destructive device definition likewise states that it "shall not include any device which is neither designed nor redesigned for use as a weapon," along with signaling and safety devices, certain surplus ordnance, and rifles the owner intends to use solely for sporting purposes. Each exclusion is narrow, and claiming one requires proof, but the government cannot treat every old, odd, or oversized object as a regulated firearm.
The five things the government must prove under § 5861(d)
The Fifth Circuit's pattern jury instruction for a subsection (d) possession case breaks the charge into five elements, each of which the government must prove beyond a reasonable doubt. Other circuits word their instructions differently, so treat this as an example of how courts structure the charge, not a nationwide script. The instruction states: "Title 26, United States Code, Section 5861(d), makes it a crime for anyone knowingly to possess [receive] certain kinds of unregistered firearms."
First: "That the defendant knowingly possessed [received] a firearm." Knowing possession means awareness. Holding a bag without knowing what is inside it, or a weapon left in a shared space you never controlled, can fail this element.
Second: that the weapon fits one of the section 5845 definitions, such as a shotgun with a barrel under 18 inches. This is where measurements, operability, and category fights happen.
Third: "That the defendant knew of the characteristics of the firearm," for example the short barrel length. This is the knowledge requirement discussed in the next section, and it is usually the most fought element.
Fourth: that the weapon was in operating condition or readily restorable to it. A rusted relic incapable of firing and incapable of being readily restored to fire may not qualify, though the government often argues restoration would have been easy.
Fifth: "That this firearm was not registered to the defendant in the National Firearms Registration and Transfer Record." The registry record is the evidence. If the weapon is registered to the defendant, the subsection (d) charge fails even if other paperwork is messy.
Knowledge cuts both ways, and you need to understand both edges
This statute has an unusual shape. It punishes possession of an object whose regulated status depends on physical facts, like barrel length or firing mechanism, that a person might not know. The Supreme Court addressed that problem in Staples v. United States, and the Justice Manual carries the result as standing prosecution policy. The Manual states that "the government must prove that the defendant knew of the features or characteristics of the weapon that brought it within the scope of the criminal proscription," and that "in all cases prosecuted under the NFA, the government must prove that the defendant knew the features of the firearm that brought it within the scope of the Act."
That is the defense edge. A person who genuinely did not know the barrel had been cut, who bought a device without knowing it functioned as a silencer, or who held parts without knowing they met the conversion-part definition may lack the knowledge the law requires. Prosecutors typically try to prove this knowledge through the obviousness of the feature, the defendant's statements, prior experience with weapons, or efforts to hide the item. Each of those proof routes can be tested, and your own words to investigators are usually the government's best evidence, which is why silence and counsel come first.
The other edge cuts against defendants. The Fifth Circuit's instruction states plainly: "It does not matter whether the defendant knew that the firearm was not registered or had to be registered." Ignorance of the registration system is no defense. The Supreme Court held this decades ago for this statute, and the instruction still carries it. So the fight is about what you knew about the object in your hands, never about whether you knew the National Firearms Act existed.
Penalties under § 5871: the maximum and what it is not
Section 5871 sets one penalty for every violation of the chapter: "Any person who violates or fails to comply with any provision of this chapter shall, upon conviction, be fined not more than $10,000, or be imprisoned not more than ten years, or both."
Ten years is a ceiling, not a forecast. There is no mandatory minimum anywhere in this statute, which means the court can impose anything from probation up to the maximum depending on the guideline range and the facts. Say this plainly because it matters: every number on this page is a statutory maximum or a guideline range. None of them predicts your sentence. Judges weigh the guideline range against the facts, the history, and the statutory purposes of sentencing. The facts of a case change everything, which is why general pages like this one cannot substitute for advice about your record and your facts. The Federal Sentencing page explains how that process works.
How the guideline works: section 2K2.1
Most NFA cases are sentenced under section 2K2.1 of the Guidelines Manual. The guideline's own commentary lists "26 U.S.C. § 5861(a)–(l)" among its statutory provisions, which confirms this is the governing guideline for every subsection of the prohibited-acts statute. Understanding its shape helps you understand what your lawyer is fighting about.
The starting point for an NFA case is usually level 18: "18, if the offense involved a firearm described in 26 U.S.C. § 5845(a)." That level applies because of the weapon itself, regardless of criminal history. It rises fast with prior record. A defendant with one prior felony conviction for a crime of violence or a controlled substance offense starts at level 20, or level 22 if the case also involves one of these weapons. With two such prior convictions, the start is level 24, or level 26 with the weapon combination. A defendant who was simply a prohibited person at the time starts at level 14, and the catch-all is level 12.
Then come the specific offense characteristics, and several land hard on NFA cases:
Number of weapons. "If the offense involved three or more firearms, increase as follows," with a table running from 2 extra levels for 3 to 7 weapons up to 10 extra levels for 200 or more. Each unregistered weapon can also be charged as its own count.
Destructive devices. A portable rocket, missile, or launcher adds 15 levels. Any other destructive device adds 2 levels.
Stolen weapons and serial numbers. "Any firearm was stolen, increase by 2 levels," whether or not the defendant knew it was stolen. A weapon with a modified serial number, or an unmarked weapon the defendant knew about or deliberately avoided knowing about, adds 4 levels.
Connection to another crime. A defendant who "used or possessed any firearm or ammunition in connection with another felony offense" receives 4 extra levels, rising to at least level 18. This enhancement is common when the weapon is found alongside drugs or during another alleged crime.
Trafficking behavior. Moving weapons to prohibited people or people who will use them unlawfully adds levels, with larger increases for multiple weapons going to people with violent, drug, or domestic violence histories.
The cross reference. If the weapon was used in connection with another offense, the court applies the guideline for that other offense when it produces a higher level. A possession case can therefore be sentenced as something more serious if the facts support it.
One reduction exists. A defendant who "possessed all ammunition and firearms solely for lawful sporting purposes or collection" without any unlawful use can drop to level 6, though this reduction is unavailable at the higher history-driven base levels. For inherited collections and hobbyists, this provision is often the most important paragraph in the guideline, and it turns on evidence of purely lawful purpose.
Defenses that actually arise under this statute
Every case is different, but defenses in NFA cases cluster around the elements above. Each one attacks something specific to this registration-based law, which is what makes them unique to this page rather than generic criminal defense.
Attack knowledge of the characteristics. The government must prove you knew the features that made the weapon regulated. Shortened barrels discovered only by precise measurement, devices whose function was not obvious, and parts whose legal significance a layperson would not grasp all create room here. Because your statements are the government's favorite proof, saying nothing until you have counsel protects this defense first.
Attack the weapon's status. Is the barrel really under the legal length, measured correctly? Was the weapon operable or readily restorable? Does an exclusion apply: antique, collector piece, signaling device, sporting shotgun, or a device neither designed nor redesigned as a weapon? If the object is not a section 5845 firearm, there is no NFA charge at all.
Attack possession. The government must tie the weapon to you through more than nearness. Shared homes, shared vehicles, and weapons found during searches of other people's property all weaken possession. If officers found the weapon through a questionable stop or search, a suppression motion can remove it from the case entirely.
Attack the registry element. The charge requires proof the weapon was not registered to you in the National Firearms Registration and Transfer Record. Registry records can be wrong, transfers can be mid-process, and trust or estate paperwork can be misunderstood by agents. The record itself must be checked, not assumed.
Raise the serial-number distinction. Subsections (h) and (i) punish weapons with obliterated or missing serial numbers as separate prohibited acts. If the weapon has an intact factory serial number and the dispute is only about registration, the case stays in subsection (d) and the government cannot stack a serial-number charge on top.
Challenge the count structure. Each weapon can be a separate unit of prosecution, which multiplies exposure fast. Counsel should test whether the indictment slices one course of conduct into more counts than the law allows, and whether group holdings like matched sets or parts kits are being overcounted at sentencing under the weapon-number table.
How this charge differs from its closest neighbours
Federal gun law stacks several overlapping crimes, and confusing them is easy. Three distinctions matter most.
Possession of an unregistered machinegun versus possession of a machinegun, period. Section 5861 punishes the failure to register and pay tax. Section 922(o) of Title 18 separately bans transferring or possessing machineguns made after May 19, 1986, outright. The Justice Manual explains why the two overlap but do not duplicate: "Section 922(o) of Title 18 makes it unlawful to transfer or possess a machinegun made after May 19, 1986," and "because it is impossible to comply with the registration and taxation provisions in the NFA, prosecutors should charge the unlawful possession or transfer of a machinegun made after May 19, 1986 under § 922(o)." In plain terms, a newer machinegun cannot be registered at any price, so the charge is the ban, not the missing paperwork. Older, lawfully registered machineguns live under the NFA system instead. See Machinegun Charges for the other half of that pair.
Registration versus status. Section 5861 asks about the weapon and the registry. Section 922(g) asks about the person: certain people, including convicted felons, cannot possess any gun at all. One arrest can produce both charges, for example an unregistered short-barreled rifle found in the hands of a person with a felony record, but they are different crimes with different elements. See Felon in Possession.
Making versus dealing. Building or converting a regulated weapon without approval violates subsection (f): "to make a firearm in violation of the provisions of this chapter." Selling guns as a business without a license is a separate charge under a separate statute. Home-built silencers and converted rifles most often draw the making charge, while repeat sellers draw the dealing charge. See Unlicensed Firearms Dealing.
If you are facing this charge now
Do not touch the weapon to fix it, sell it, move it, or destroy evidence. Each of those acts can add charges: making, transferring, false entries, or obstruction. Do not try to explain the weapon to agents. Explanations become admissions about knowledge and possession, the two elements the government most needs from your mouth.
These cases are usually investigated by the Bureau of Alcohol, Tobacco, Firearms and Explosives. The Justice Manual states the reason simply: "The Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) has primary investigative jurisdiction over violations of the Federal firearms statutes." If ATF agents are involved, read about ATF investigations and get counsel before deciding where and how to engage.
Gather paperwork instead, and give it only to your lawyer. Any registration forms, transfer approvals, trust or estate documents, receipts showing how and when you got the weapon, and photographs showing its condition when you received it are the raw materials of the defenses above. Write down privately, for your lawyer only, who had access to the weapon and when, and what you knew about its features.
Then get an assessment of the three questions that drive every one of these cases: is the object actually a regulated firearm, can the government prove you knew its regulated features, and what does the registry record show. Everything else, from negotiation to motions to sentencing preparation, flows from those answers.
This page is general information, not legal advice. The statute, the guideline, and the policies cited here are starting points. Your district, your record, and your facts decide what they mean for you.