Knife Laws in Montana

Rebecca Hanlon
Last Updated: March 4th, 2023

Though most knife laws in Montana are direct, there are few exceptions and intriguing corner cases. In general, knife laws continuously vary among states, as different state governments individually assess their danger and benefits. For instance, until recently, switchblades were illegal in Montana for everyone except collectors. Similarly, concealed carry was also unlawful for most knives, except those less than 4 inches in length or found in certain regions.

Needless to say, state laws are constantly changing due to new legislation, federal decisions, and similar factors. So, if you’re looking for a quick way to remain up-to-date with the latest knife laws in Montana, you’ve come to the right place. We’ll help cover all the general legalities; however, we recommend consulting an attorney for more detailed research.

Hidden Knives are Forbidden

hidden knives

Up until recently, Montana had strict knife laws for weapon concealment. These laws dictated that knives exclusively were not allowed to be hidden. And many variations, such as sword canes, switchblades, and blades longer than 4 inches, were illegal or difficult to get a hold of.

However, new laws indicate that only firearms aren’t to be concealed, making the possession of most knives legal. As a result, with the correct licenses under these laws, a person could even have unlimited concealed carry.

Relevant Statutes and Legal Definitions

We recommend looking into official resources to know more about the specifics of state laws. As a result, you should check out the following statutes on the official site of the Montana State Legislature.

  • MCA 45-8-361
  • MCA 45-8-315
  • MCA 45-8-352
  • MCA 45-2-101

The statutes above generally cover all you need to know about knife laws in Montana. However, they might be misleading without the required definitions for some legal terms.

Consequently, the following are general definitions for some recurring keywords:

(43) Negligently – A “negligent” action counts as a risk consciously committed. This could also apply to instances in which a person doesn’t consider a circumstance that could exist. In general, it’s a term used to describe irresponsible use.

(35) Knowingly – Legally, the state of Montana deems people liable if they commit an offense “knowingly.” Generally, this means that the actions would be considered an offense only if the person is aware of the consequences of their conduct.

(66) Serious bodily injury – A “serious bodily injury” caused by a weapon could include:

  • An injury resulting in permanent or prolonged damage
  • An injury that results in a significant risk of death
  • An injury that, momentarily, results in a substantial fear of death or permanent damage

Similarly, this term can also be used to describe mental impairment that results from an injury. For example, diagnosed symptoms of Post-traumatic Stress Disorder (PTSD) caused due to a violent attack.

(79) Weapon – By state law, knives and guns aren’t the only things covered under the definition of a “weapon.” Overall, any article, instrument, or substance that can cause serious bodily injury or death is considered a weapon; regardless of what it’s primarily used for.

(59) Possession – A person is in “possession” of a weapon only if it is kept under their control knowingly for a sufficient amount of time.

Recent Annotations

As brushed upon earlier, Montana has recently made sizable changes to its knife laws. The most notable changes of which are the annotated 2017 and 2019 amendments.

Annotated 2017

As of 2017, Montana amended its knife laws by getting rid of the legal definition of a concealed weapon. Before the new law, it was defined as “a knife with a blade 4 inches or more in length that is wholly or partially covered by the closing or wearing apparel of the person carrying or the weapon.” (45-8-315, n.d.)

However, with recent changes, there are no current restrictions on the concealment of knives for use in self-defense in an outdoor environment. Similarly, the annotation stopped the ban on unique knives, such as sword canes, daggers, or dirks.

Annotated 2019

On April 3rd, 2019, the state government removed the restriction on the possession and use of automatic knives or switchblades. However, the exception was that the switchblades had to be limited to one and a half inches.

Additionally, this annotation brought an immense win for local knife enthusiasts. Through section HB 155, the annotation stated that the “local government may not enact or enforce an ordinance, rule, or regulation that restricts or prohibits the ownership, use, possession, or sale of any type of knife that is not specifically prohibited by state law.” (House Bill No. 155, n.d.)

In essence, this meant that all knives previously allowed would never be banned. This ensures that all citizens are protected by state laws and that the safe use of automatic knives is encouraged.

Specifics of Concealed Carry of Knives

carry of knives

The Montana Annotated Code, section 45-8-316, states that it’s illegal to carry a concealed blade if its length is 4 inches or longer. What’s important to note here is that the knife has to be less than four inches; a four-inch knife is illegal to be partially or wholly hidden. Additionally, this section states that it’s legally acceptable for a blade four inches or more to be found inside an owner’s vehicle or to be openly exposed.

However, as somewhat described earlier, section 45-8-317 (Annotation 2017) changes these laws exceptionally. It does so by describing a series of broad exceptions for concealing knives. These include ranching, farming, hiking, hunting, fishing, trapping, backpacking, or similar outdoor activities. And, generally, these laws encourage the use of knives for numerous kinds of utilities or personal protection in an outdoor environment.

Where Can You Not Have a Concealed Knife?

Though the new knife laws in Montana dictate that practically any knife is allowed, there are few exceptions, although these are explicitly mentioned and are generally expected. For instance, you are strictly not allowed to conceal a knife in federal buildings or schools.

In particular, it’s considered a crime for anyone who knowingly or unlawfully possesses any weapon on school premises. Likewise, if a parent or guardian allows their child (a minor) to carry a knife or a similar deadly weapon into a school knowingly and unlawfully, that would also be illegal.

However, there are certain grey areas for knife laws in Montana too. For instance, it’s legally questionable to conceal knives in places that serve alcohol openly or in local government and financial institutions.

Why Is There A Discrepancy For Federal Buildings?

Though the statute explicitly mentions that knives are prohibited in schools, it doesn’t include federal buildings. So then why are they banned? Since the statute was explicitly expressed under state laws, federal buildings are excluded as they’re governed by federal law.

Exceptions to Knife Laws in Montana

knife laws

In general, Montana exempts numerous classes of people from the concealed carry law. This includes the general public, along with the concealed carry of weapons for certain government employees.

Consequently, concealed carry is only restricted to people outside the state. In these cases, outsiders would only be allowed to hide their weapons in lawful recreational activities or inside their home or office space.

Similarly, exceptions also exist for possession in school buildings and other restricted areas. But, they are only granted to law enforcement personnel or trustees of the district.

Statewide Pre-emptions

Legally, local governments are only allowed to restrict the possession of knives on property leased or owned by a government entity. But, other than that, the government cannot enforce any restriction on the control, use, ownership, or sale of knives.

Penalties of Knife Law Violations

Since there aren’t many restrictions for holding knives, you can expect some serious consequences. For a person who violates the law by bringing concealed knives into schools or other restricted areas, you can expect imprisonment in county jail for up to 6 months or a fine of up to $500.

However, the punishments can also be more severe depending on the perpetrator. Previous offenders can instead receive imprisonment in a state jail for up to five years and a fine of $1000. Similarly, an injury caused by a knife would be considered an offense and treated accordingly.

Final Thoughts

Knife laws in Montana have generally undergone immense changes to become more lenient to the public for their safety and benefit. Through the enactment of the 2017 and 2019 annotations, almost everyone can use knives to protect themselves. These recent changes encourage the safe use of knives while punishing only offenders.

Likewise, through knives being restricted in school, the state shows its intent to protect minors from dangerous influences. Further illustrating how the laws are working towards creating a safer community.

That being said, it’s worth noting that officials tend to have different interpretations of knife laws. What might be legal in some districts might be considered illegal in others. As a result, we again stress the importance of consulting a lawyer or government official as a formal resource.

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About The Author

Rebecca Hanlon

Rebecca has been a travel blogger and editor for over 5 years, working with some of the biggest brands in industry. She’s taught English as a foreign language in 5 different countries, and her most fulfilling role was as a tour guide around some of Europe’s finest vineyards. She the one behind the social channels here at Discovering Montana, whilst also finding the time to perform an assistant editor role.

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