Are Brass Knuckles Legal in Montana? (2026 Weapons Law)

Montana's general concealed-weapons law does not cover brass knuckles. The Montana Code Annotated defines a "concealed weapon" as a firearm (MCA 45-8-315), and the concealed-carry offense in 45-8-316 punishes carrying a concealed firearm. The two weapons statutes that do name knuckles are each limited to a place or a group of people: a ban on brass or other metal knuckles in school buildings (45-8-361) and a felony for prisoners who possess knuckles (45-8-318).

That means the main limits on knuckles in Montana are where you take them and how they are used, not ownership by itself. For other states, see our guide to brass knuckles laws by state.

Information last verified on 2026-10-08. This article has not been reviewed by a licensed lawyer.

Jurisdiction scope: This article covers Montana state statutes in Title 45, chapter 8, part 3 of the Montana Code Annotated (sections 45-8-315, 45-8-316, 45-8-318, 45-8-328, 45-8-351, 45-8-352 and 45-8-361), the general weapon definition in 45-2-101, the transferring-illegal-articles offense in 45-7-307 and the weapon sentence enhancement in 46-18-221. It does not cover Montana court decisions, city or county ordinances (apart from one Billings example), college and university policies, school district discipline rules, federal law or federal property, or the law of other states.

Does Montana law ban brass knuckles?

Montana's Code names knuckles in two weapons statutes, and neither is a general ban:

• School buildings. Section 45-8-361 lists "brass or other metal knuckles" among the weapons a person may not possess, carry or store in a school building.
• Prisoners. Section 45-8-318 lists "knuckles made of any metal or hard substance" among the deadly weapons a prisoner may not possess without lawful authority.

Outside those settings, the statutes that set Montana's everyday carry rules are written around firearms. Neither the concealed-weapon definition in 45-8-315 nor the offense in 45-8-316 mentions knuckles, and the local-regulation statute, 45-8-351, limits what cities and counties can do about weapons in general (see below).

Carrying knuckles concealed or openly

Montana's concealed-carry offense starts with a definition that is limited to guns:

"'Concealed weapon' means a firearm that is wholly or partially covered by the clothing or wearing apparel of the person carrying or bearing the weapon." MCA 45-8-315

The offense itself is also written for firearms:

"(1) A person who carries or bears concealed upon the individual's person a firearm shall be punished by a fine not exceeding $500 or by imprisonment in the county jail for a period not exceeding 6 months, or both." MCA 45-8-316(1)

Because both sections speak only of firearms, carrying knuckles in a pocket is not the 45-8-316 offense. The same defined term appears in 45-8-328, which makes it an offense to carry "a concealed weapon" into restricted portions of a building used for state or local government offices, punishable by up to 6 months in the county jail, a $500 fine, or both. That section uses the same term 45-8-315 defines as a firearm.

None of this makes knuckles safe to carry everywhere. The school-building ban and the prisoner felony apply whether the knuckles are hidden or in plain view, and using knuckles against another person brings in other offenses and the sentence enhancement covered below. When force is lawful at all is covered in our guide to Montana self-defense laws.

Brass knuckles in Montana schools

Section 45-8-361 is the Montana statute an ordinary person is most likely to run into:

"(1) A person commits the offense of possession of a weapon in a school building if the person purposely and knowingly possesses, carries, or stores a weapon in a school building. ... (4) (a) A person convicted under this section shall be fined an amount not to exceed $500, imprisoned in the county jail for a term not to exceed 6 months, or both." MCA 45-8-361

For this section, a weapon means "any type of firearm, a knife with a blade 4 or more inches in length, a sword, a straight razor, a throwing star, nun-chucks, or brass or other metal knuckles. The term also includes any other article or instrument possessed with the purpose to commit a criminal offense" (45-8-361(5)(b)).

Two points about the wording:

• Material. The listed item is "brass or other metal knuckles." Knuckles made of plastic or another non-metal material are not in that list, though the closing sentence reaches any article "possessed with the purpose to commit a criminal offense."
• Place. The offense applies in a school building, which the section defines as a building owned or leased by a local school district and used for instruction or for student activities. The definition excludes a home school.

The same section makes it a separate offense, with the same penalty, for a parent or guardian to purposely and knowingly permit a minor to possess, carry or store a weapon in a school building (45-8-361(2)). The ban in subsection (1) does not apply to law enforcement personnel or to a school marshal in the district that employs or contracts with the marshal, and a district's trustees may grant advance permission to possess, carry or store a weapon in a school building (45-8-361(3)).

Jails, prisons and people in custody

Montana treats knuckles in custody as a serious felony:

"(1) A person commits the offense of possession of a deadly weapon by a prisoner if the person purposely or knowingly possesses or carries or has under the person's custody or control without lawful authority a dirk, dagger, pistol, revolver, slingshot, sword cane, billy, knuckles made of any metal or hard substance, knife, razor not including a safety razor, or other deadly weapon while the person is: (a) a person committed to a state prison or incarcerated in a county jail, city jail, or regional jail ..." MCA 45-8-318(1)

The penalty is "imprisonment in the state prison for a term not less than 5 years or more than 15 years, by a fine of not more than $50,000, or by both fine and imprisonment" (45-8-318(2)). Unlike the school statute, this section covers knuckles of "any metal or hard substance," not only metal ones. The same offense covers a person in a youth detention facility, secure detention facility, regional detention facility, short-term detention center, correctional facility or shelter care facility, as defined in 41-5-103 (45-8-318(1)(b)). The youth court has jurisdiction of that charge unless it is filed in district court (45-8-318(3)).

People outside the facility face a separate felony. Under 45-7-307, a person who knowingly or purposely transfers "any illegal article or weapon" to a person subject to official detention commits the offense of transferring illegal articles, punishable by up to 20 years in a state prison when the item is a weapon. That section does not list knuckles by name. Montana's general definition of "weapon" in 45-2-101, which applies unless a statute specifies otherwise, is "an instrument, article, or substance that, regardless of its primary function, is readily capable of being used to produce death or serious bodily injury."

Using knuckles in a crime

Section 46-18-221 adds prison time when a person, while committing an offense, "knowingly displayed, brandished, or otherwise used a firearm, destructive device, as defined in 45-8-332 (1), or other dangerous weapon." The added term is "not less than 2 years or more than 10 years" in the state prison, on top of the sentence for the underlying offense. The added term must run consecutively, and its minimum may not be deferred or suspended except as provided in 46-18-222. A second or subsequent offense under the section carries 4 to 20 additional years. The enhancement does not apply to an offense in which use of a weapon is already an element. The statute does not say whether knuckles count as an "other dangerous weapon," and this article does not discuss any Montana court decision on that question.

Can Montana cities or counties regulate knuckles?

Montana limits local weapons rules broadly. Section 45-8-351 is not confined to firearms:

"(1) Except as provided in subsection (2), a county, city, town, consolidated local government, or other local government unit may not prohibit, register, tax, license, or regulate the purchase, sale or other transfer (including delay in purchase, sale, or other transfer), ownership, possession, transportation, use, or unconcealed carrying of any weapon, including a rifle, shotgun, handgun, or concealed handgun." MCA 45-8-351(1)

The exception in subsection (2)(a) lets a city or town regulate the discharge of rifles, shotguns and handguns, and gives local governments "power to prevent and suppress the carrying of unpermitted concealed weapons or the carrying of unconcealed weapons to a publicly owned and occupied building under its jurisdiction." Section 45-8-351 does not define "weapon," and this article does not discuss any Montana court decision applying the 45-2-101 definition to it.

Billings is one city that uses this building power for knuckles. Billings City Code section 18-204 prohibits any person other than law enforcement from possessing "brass or metal knuckles," openly or concealed, in a city building, which the code defines to include the exterior entrance and exit areas serving the building. A violation is punishable by a fine of up to $500, up to 6 months of imprisonment, or both.

Knives have their own preemption statute, 45-8-352, which bars local rules restricting "any type of knife that is not specifically prohibited by state law," except rules on knives in buildings or on property owned, leased or possessed by the local government. Knife rules are covered in our guide to Montana knife laws.

If you are unsure whether a local rule applies to a public building, check the city or county code or call your local police department's non-emergency line.

Montana penalties at a glance

The last two rows apply to knuckles only if they fall within the term the section uses.

Related pages

• Brass knuckles laws by state
• Montana knife laws
• Montana self-defense laws
• Montana pepper spray and stun gun laws
• Idaho brass knuckles laws

This article provides general legal information about Montana state law, not legal advice. Weapons laws change and local building rules vary. For advice about a specific situation, contact a lawyer licensed in Montana or your local law enforcement agency.

Last updated: 2026-10-09.

Frequently Asked Questions

Are brass knuckles legal in Montana?

Montana's Code names knuckles in two weapons statutes, and both are limited: 45-8-361 bans them in school buildings and 45-8-318 bans them for prisoners. The concealed-weapon offense in 45-8-315 and 45-8-316 is defined in terms of firearms, so it does not reach knuckles.

Can I carry brass knuckles concealed in Montana?

Montana's concealed-carry offense, 45-8-316, punishes carrying a concealed firearm, and 45-8-315 defines a concealed weapon as a firearm. Knuckles are still banned in school buildings under 45-8-361, and using them in a crime can bring other charges and a sentence enhancement under 46-18-221. Under 45-8-351(2)(a), a local government may also act against weapons carried into a publicly owned and occupied building under its jurisdiction; Billings, for example, bans knuckles in city buildings.

Can I bring brass knuckles into a Montana school?

No. Purposely and knowingly possessing, carrying or storing brass or other metal knuckles in a school building is an offense under 45-8-361, punishable by up to a $500 fine, 6 months in the county jail, or both. The section defines a school building as a building owned or leased by a local school district and used for instruction or student activities. A parent or guardian who purposely and knowingly permits a minor to do so commits a separate offense with the same penalty. The ban does not apply to law enforcement or a school marshal, and a district's trustees may grant advance permission.

Can a Montana city ban brass knuckles?

Under 45-8-351(1), a county, city or town may not prohibit, register, tax, license or regulate the purchase, sale, ownership, possession, transportation, use or unconcealed carrying of any weapon. Under 45-8-351(2)(a), a local government may still prevent and suppress the carrying of unpermitted concealed weapons, or of unconcealed weapons, into a publicly owned and occupied building under its jurisdiction. Billings City Code section 18-204 uses that power to ban knuckles in city buildings.

What is the penalty for a prisoner caught with knuckles in Montana?

Possession of a deadly weapon by a prisoner, which names knuckles made of any metal or hard substance, carries 5 to 15 years in the state prison, a fine of up to $50,000, or both under 45-8-318(2).