Why Are Butterfly Knives Illegal?

Last Updated on May 19, 2023 by River Tree Farms

Did you know that butterfly knives are illegal in some parts of the world? The controversial knives date as far back as 1710. They were first recorded in the French book “Le Perret” as Balisong Knives. In the United States, there are legal restrictions, especially in states with strict regulations on knife possession. Knives are highly associated with crime. If you have asked the question ‘why are butterfly knives illegal?’ Keep reading to find out. 

Knife Laws Vary

Knife laws are complicated, and they change depending on where you live. What is perfectly legal in one part of the world could be illegal elsewhere. This is important to keep in mind, especially if you travel a lot. Your pocket knife could be considered a dangerous weapon in some places. 

If you are concerned about the legality of different types of knives, your best bet is to opt for those that are originally designed for utility. Swiss Army knives, for example, are unlikely to be illegal regardless of where you go. In addition, do not buy knives that are longer than three inches. They may be considered deadly weapons. 

What Are Butterfly Knives?

The main feature of butterfly knives is that they come with two handles rotating around the tang. When closed, the knife’s handle conceals the blade. The knife quickly opens to reveal the blade, and if you aren’t careful, you can easily get hurt. 

Training butterfly knives exist to help you practice how to whip the knife open without cutting a finger off. 

The knives were initially created for self-defense but later became popular among criminals. Before their popularity, they even served as pocket utility knives and razor blades. 

Are Butterfly Knives Illegal?

Yes, butterfly knives are illegal for a pretty good reason. First, they have a high potential of being used as threatening weapons. Anyone with some practice can deploy them at high speed and cause significant damage. The speed at which the knives can be drawn and withdrawn is one of their most dangerous qualities. They have a history of being used by criminals. 

They are illegal knives as most states classify them as such. Usually, the illegality of a knife depends on whether it is classified as a switchblade knife, gravity knife, or dagger. 

States that Prohibit Butterfly Knives

The knives are illegal in eight states. However, the degree of legality varies as follows:

  • Wisconsin: You are legally permitted to have the knives on your property
  • Texas: the possession of butterfly knives is forbidden
  • Hawaii: the knives are forbidden
  • Utah: the knives are forbidden in the state of concealment
  • California: since you can’t legally possess a knife that is more than two inches long, butterfly knives are illegal
  • Oregon: the knives are forbidden in the state of concealment
  • New York: If you are a resident, you can legally own butterfly knives. However, visitors aren’t allowed to carry them.
  • Kansas: Butterfly knives are restricted

States Where Butterfly Knives Are Legal:

Some states have made butterfly knives legal. They are also legal in various parts of the world. If you are a knife enthusiast, you’d be wise to stay informed on knife laws and how they keep changing depending on where you live. 

Butterfly Knives Laws on Federal Property

Even in parts of the United States where butterfly knives are legal, you’ll still run into restrictions when on federal property. You cannot bring a butterfly knife to any federal location. The only exception is if you are a federal agent. 

According to the federal switchblade law, any kind of blade that is considered a switchblade is forbidden from federal property. If you break the law, you may be punished under federal law. 

How Dangerous Are Butterfly Knives?

The design of butterfly knives is the main reason why they are so dangerous. If they are sharpened, and you attempt to perform tricks like ‘aerial’ stunts, you are likely to injure yourself. It is important to get some training before you flip, spin, or roll the knives. The fact that they are so easy to conceal makes the knives ideal for criminal activity. 

Knife Laws, Penalties, and Offences

The penalties for going against knife laws vary depending on where you live. Common violations include:

  • Owning a butterfly knife is against the state laws
  • Concealing a knife where the state demands that it be carried openly
  • Brandishing the knife as a weapon. This may include wielding it aggressively or in a fight
  • Using the knife to inflict physical injury

What Are the Legal Defenses?

There are a few instances when you can legally carry a butterfly knife. If you have been charged in violation of knife laws, here are a few legal defenses to get you out of trouble. 

  • The first and arguably most helpful defense is that no violation happened. If you can prove that you weren’t in violation of the law, you cannot be convicted.
  • If you have been charged with concealing the knife, a good defense would be that you were following the open carry law. 
  • If you can prove that you carried the knife unknowingly, it could also be a useful defense. The prosecutor has to prove that you knew the knife is prohibited and that you knew it was in your possession. If they can’t provide this proof, they may have to drop the charges. 
  • If the knife was found during an illegal search, it cannot be used as evidence against you during a trial. 


Why are butterfly knives illegal? While there is no clear answer, knives have widely been associated with criminal activity. They can cause significant damage even though they may not look dangerous. In many parts of the world, butterfly knives are considered threatening weapons. 

If you travel a lot or are a knife enthusiast, you’d be wise to learn about the different knives and their legality in different parts of the world. If you already possess a butterfly knife, learn how to use it safely. Otherwise, you may injure yourself and others.