26 USC 5861: NFA Prohibited Acts, Penalties, and Forfeiture

Section 5861 of Title 26 of the U.S. Code lists twelve prohibited acts involving firearms regulated under the National Firearms Act. Each violation carries up to ten years in federal prison and a fine that can reach $250,000 for an individual under the general federal sentencing statute. The prohibited acts under 26 U.S.C. 5861 run from possessing an unregistered NFA firearm, to building or transferring one without approval, to grinding off a serial number, to lying on an ATF form. Several of them catch people who never realized they were committing a crime.¹²

Which Firearms Section 5861 Actually Covers

Every prohibition in section 5861 depends on the item meeting the NFA definition of “firearm” in 26 U.S.C. 5845. Ordinary handguns, rifles, and shotguns are not covered. The NFA reaches six categories:³

Machine guns, including the receiver of such a weapon, conversion parts, and any combination of parts from which a machine gun can be assembled.
Short-barreled rifles, meaning rifles with a barrel under 16 inches or an overall length under 26 inches.
Short-barreled shotguns, meaning shotguns with a barrel under 18 inches or an overall length under 26 inches.
Suppressors.
Destructive devices, including bombs, grenades, mines, rockets with a charge over four ounces, and weapons with a bore diameter exceeding one-half inch (except sporting shotguns).
“Any other weapons,” a catch-all covering concealable devices that fire a shot using explosive energy but don’t fit the other categories. Pen guns and smooth-bore pistols designed for shotgun shells are common examples.

If the item doesn’t fall into one of these categories, section 5861 doesn’t apply. Once it does, every offense below becomes relevant.

Possession and Registration Offenses

The National Firearms Registration and Transfer Record tracks every NFA firearm from manufacture or import through every subsequent transfer. Three of the twelve prohibited acts turn on that registry:¹

Subsection (d) makes it a crime to possess an NFA firearm that isn’t registered to you in the Record. This is the most frequently charged NFA offense. How you got the item — built, bought, found, inherited — is not a defense.
Subsection (c) makes it a crime to receive or possess an NFA firearm made in violation of the NFA. If someone else built the item improperly, later possessors commit a separate offense.
Subsection (b) makes it a crime to receive or possess an NFA firearm transferred in violation of the NFA.

Possession here is broader than holding the item. Courts recognize constructive possession, meaning conviction is possible when a person had the power and intent to control the item without ever touching it. An unregistered suppressor sitting in a safe the defendant controls can support a section 5861(d) charge as easily as one in a bag on the defendant’s shoulder.

Making and Transferring Offenses

Building or moving an NFA firearm without ATF approval is a separate crime from possessing one. Subsection (f) makes it illegal to make an NFA firearm in violation of the NFA, and subsection (e) makes it illegal to transfer one in violation of the NFA.¹ Legal making requires prior approval on ATF Form 1; legal transfer requires prior approval on ATF Form 4.⁴

These offenses stack with the possession offenses. Someone who builds an unregistered short-barreled rifle at home is exposed to a charge for making without approval and a separate charge for possessing the unregistered finished product. An unauthorized sale triggers subsection (e) for the seller and subsection (b) or (d) for the buyer.

The registration duty exists regardless of whether the item carries a tax. Machine guns and destructive devices carry a $200 making or transfer tax; suppressors, short-barreled rifles, short-barreled shotguns, and any-other-weapons currently carry a $0 tax.⁵⁶ Skipping the paperwork is the crime, whether or not money is owed.

Serial Number and Identification Offenses

Federal law requires every NFA firearm other than a destructive device to carry a serial number and the name of the maker or manufacturer, in a form that cannot be easily removed.⁷ Three prohibited acts protect those markings:¹

Subsection (g): removing, changing, or destroying the serial number or other required markings on an NFA firearm.
Subsection (h): possessing an NFA firearm whose markings have been altered or removed, even if someone else did the tampering.
Subsection (i): possessing an NFA firearm that never had the required identification in the first place.

These offenses are independent of registration status. A properly registered suppressor whose serial number has been ground off supports a felony charge even though the underlying registration is valid.

Business, Interstate, Import, and Recordkeeping Offenses

The remaining prohibited acts surface most often in commercial enforcement but carry the same maximum sentence.

Subsection (a) covers acting as a manufacturer, importer, or dealer of NFA firearms without paying the special occupational tax. That tax runs $1,000 per year for manufacturers and importers, and $500 per year for dealers, with a reduced rate for small businesses.⁸

Subsection (j) prohibits transporting or receiving any unregistered NFA firearm across state lines. Subsection (k) targets NFA firearms imported in violation of 26 U.S.C. 5844, which limits importation to government use, scientific research, and testing by licensed manufacturers and dealers.⁹ Private citizens generally cannot import NFA firearms at all.

Subsection (l) criminalizes making a false entry on any NFA application, return, or record when the person knows the entry is false. It is the only prohibited act in section 5861 that spells out a knowledge requirement in the statute itself. Lying on a Form 1 or Form 4 carries the same ten-year maximum as any other NFA violation.

What the Government Has to Prove

An NFA conviction requires more than proof of possession. In Staples v. United States, 511 U.S. 600 (1994), the Supreme Court held that the government must prove the defendant knew the weapon had the specific characteristics that brought it under the NFA.¹⁰ The defendant’s AR-15 had been internally modified to fire automatically, and the Court held that the government had to prove he knew about the automatic-fire capability, not just that he knew he had a rifle.

That rule matters. A person who inherits a rifle without realizing a previous owner shortened the barrel below 16 inches has a real defense. So does a person who acquires an externally normal-looking weapon that had been internally converted. The government cannot rely on the fact that the item qualifies as an NFA firearm and was in the defendant’s possession. It must connect the defendant’s knowledge to the physical features that trigger regulation.

The knowledge rule stops there. The government does not have to prove the defendant knew the item was unregistered, or that the defendant had ever heard of the NFA. Knowledge of the item’s characteristics is the issue; knowledge of the law is not.

Penalties, Forfeiture, and Stacked Charges

Every violation of section 5861 carries the same penalty under 26 U.S.C. 5871: a fine of up to $10,000, imprisonment for up to ten years, or both.² The fine can go higher in practice. The general federal sentencing statute allows fines up to $250,000 for individuals and $500,000 for organizations convicted of a felony, and courts apply whichever maximum is greater.¹¹

Any NFA firearm involved in a violation is subject to seizure and forfeiture. Forfeited items are not sold back to the public. They are destroyed, transferred to a government agency, or sold to a state or local government.¹²

Because one course of conduct often violates several subsections, federal prosecutors stack charges. Building an unregistered short-barreled rifle can produce charges for making without approval, possessing an unregistered item, and possessing an item without proper identification marks. Each count carries its own ten-year ceiling. Sentencing guidelines and judicial discretion determine how the time actually runs, but the statutory exposure adds up quickly.

The Extra Rule for Machine Guns

Machine guns sit under an additional restriction outside the NFA. Under 18 U.S.C. 922(o), private possession or transfer of a machine gun is illegal unless the weapon was lawfully possessed before May 19, 1986.¹³ The pool of transferable machine guns is frozen, and market prices reflect it.

The practical consequence for section 5861 is that a private citizen who builds a machine gun today has no legal registration path. The conduct violates both 18 U.S.C. 922(o) and 26 U.S.C. 5861. Government agencies and qualified dealers with the proper licensing are exempt from the 922(o) restriction; ordinary owners are not.

1
Office of the Law Revision Counsel. 26 U.S. Code 5861 – Prohibited Acts
2
Office of the Law Revision Counsel. 26 U.S. Code 5871 – Penalties
3
Office of the Law Revision Counsel. 26 U.S. Code 5845 – Definitions
4
Bureau of Alcohol, Tobacco, Firearms and Explosives. Application for Tax Paid Transfer and Registration of Firearms (ATF Form 4 (5320.4))
5
Office of the Law Revision Counsel. 26 U.S. Code 5811 – Transfer Tax
6
Office of the Law Revision Counsel. 26 U.S. Code 5821 – Making Tax
7
Office of the Law Revision Counsel. 26 U.S. Code 5842 – Identification of Firearms
8
Office of the Law Revision Counsel. 26 U.S. Code 5801 – Imposition of Tax
9
Office of the Law Revision Counsel. 26 U.S. Code 5844 – Importation
10
Justia. Staples v. United States, 511 U.S. 600 (1994)
11
Office of the Law Revision Counsel. 18 U.S. Code 3571 – Sentence of Fine
12
Office of the Law Revision Counsel. 26 U.S. Code 5872 – Forfeitures
13
Office of the Law Revision Counsel. 18 U.S. Code 922 – Unlawful Acts