The Federal Bureau of Investigation (FBI) reports that knives are involved in 1,600 to 1,800 murders in the United States each year. Deaths from stab wounds account for 8% of total homicides, with an average rate of up to 0.5 deaths per 100,000 persons.
Different states of the United States usually have different knife laws. Even within a single state, knife laws can be different from one city or county to another. These varying laws about knife usage lead people to commit knife law infractions unknowingly. Several states have over the years relaxed laws pertaining to the carrying of knives, but restrictions still exist with respect to specific types of knives, ways to carry them, where they can be carried, and how they may be used.
For instance, owning and carrying knives in the state of New York are allowed for adults under New York knife laws, but there are levels of restrictions that apply to them. It is against the state law to be in possession of some types of knives, like ballistic knives. Using any knife improperly or with the intention of committing a crime will lead to criminal charges.
The legal consequences for carrying a knife can range from a misdemeanor to a felony, so it is extremely important to be aware of all applicable state and city laws regarding knife possession.
Acquiring an understanding of the commonly committed offenses in reference to knives can help prevent such legal mistakes and guide you to act appropriately within legal limits.
Let’s discuss the common knife law violations.
The Federal Layer: Limited but Real
There is no single federal law that governs knife carrying. One of the federal laws, the 1958 Federal Switchblade Act, concerns interstate commerce transactions involving switchblades and prohibits mailing them. This act includes exemptions for military personnel. A violation of this act could result in felony charges. According to serious crimes and felony lawyer T. Noel Brooks, the majority of felonies have no time limit, meaning a case can be filed against you at any point. It is critical to have an experienced felony lawyer ready to defend your rights whenever a charge arises.
Laws concerning ballistic knives can be found in 15 U.S.C. § 1245, which deals with the regulation of violence knives for civilian use but does not extend to other sharper knives. It is prohibited to take a knife in carry-on luggage.
Federal law comes into force especially when an individual carries a knife across the states or dispatches it via mail and freight transportation. An authorized knife could still trigger federal issues during the interstate trip if the blade matches a category that federal law bans.
Most everyday folding knives and fixed-blade knives stay outside federal reach. Automatic knives and ballistic knives remain a federal concern in interstate situations, even after a bunch of states have rolled back their bans.
Automatic and Switchblade Knives: Rapidly Changing State Law
Automatic knives have been some of the most tightly controlled knife categories at the state level. And it was restrictive everywhere. Since 2022, several states have either rolled back their switchblade rules or done so in a way that narrowed them a lot.
- Virginia decided to nullify its switchblade constraints incrementally, with the first being legislative repeal of the prohibition on possession in the year 2022. The next step is the repeal of prohibitions on concealed carry and sale in 2023.
- The ban on switchblades was terminated in Pennsylvania as of January 2023.
- In May 2024, Hawaii’s legislature reversed course under Bill HB 2342, now Act 21, and open carry of knives is now legal.
- In Massachusetts, the law has changed since the Commonwealth v. Canjura decision deemed the state’s prohibition of switchblades to be unconstitutional. It should be pointed out that there are still ongoing changes in the law so do not expect the legal rules to be fully set in stone.
- Delaware repealed its ban in July 2025 under SB 108. Blades up to 3.75 inches are now classified under the category of “Ordinary Pocketknife.” Anything bigger needs a concealed carry license.
- Vermont erased its switchblade subsection completely in June 2025 under Act 64.
Some places still either ban automatic knives or keep them under heavy restrictions. Washington, D.C. is one example with a direct ban, and several states still use blade-length caps for the concealed carry of automatics.
Connecticut keeps a 1.5 inch blade limitation for automatic knives. Checking the current rules in your state matters to avoid unwarranted legal violations.
Concealed Carry Violations: The Most Common Source of Charges
Carrying a knife concealed is handled in a different way than openly carrying it out in the open. Many states allow open carry of almost any knife, but they still put extra rules on concealed carry.
The common violation scenario is a person who carries a knife that he thinks is perfectly legal to carry but does not know about the state ban on the concealed carrying of that specific type of knife/blade.
Even in places where open carry is allowed, concealed carry limits often apply to fixed-blade knives, daggers, and dirks.
The exact blade length where concealed carry starts to get restricted is inconsistent. Some states use a cutoff at two inches, while others go with three or even four inches. A few states don’t set any blade-length limit for concealed carry, but then they restrict certain knife types outright.
Restricted Locations: Where Even Legal Knives Are Prohibited
A knife that’s completely legal to carry in public can turn into a criminal issue the second you step into a restricted place. These places usually set absolute bans, no matter how you try to carry it or what kind of blade it has:
- Schools and school grounds: State laws and school policies usually dictate that knives are not allowed in primary and secondary school buildings. The regulation differs with every state, with some specifying relevant situations, but all have some exceptions when it comes to school and occupation.
- Government buildings and courthouses: most states restrict knives inside buildings used for government business. A lot of local rules also stretch it to any building where there are metal detectors, or where they run security screening
- Airport security areas: TSA rules say no knives in carry-on bags. If something is left in your carry-on and spotted at the checkpoint, it may be confiscated. In some cases you could see a criminal referral depending on what the knife is and how it’s made
- Bars and licensed premises: many states ban weapons, including knives over certain lengths, in venues that sell alcohol and hold the proper licenses.
Committing a violation in these locations is risky for people who carry knives lawfully. For example, a contractor who is carrying a work knife in accordance with the rules and later shows up at a courthouse for a routine matter will get hit with a weapons charge.
Preemption and the Local Ordinance Problem
About twenty states have put in place statewide knife law preemption so municipalities can’t just pass knife ordinances that are stricter than the state rules. In those preemption states, a city can’t lower blade length limits or tack on extra knife categories to a do-not-allow list beyond what state law already spells out.
But in places without preemption, cities and counties may set up their own local constraints. If a knife is legal under the state framework, it can still get treated as illegal inside a particular city.
Staying Current
Knife laws have changed in the past several years more than in any other comparable window. The law regarding the legality of switchblades has undergone some radical changes within this period, arising mainly from the relaxation in the enforcement of those laws, court decisions nullifying existing restrictions, and more laws that can be classified as preemption.
The American Knife and Tool Institute’s state law database, alongside the Knife Rights Foundation, maintains regularly updated state-by-state references. You can use data from these resources to check whether knife possession is legal in certain circumstances and locations.
If you’re planning to carry in a location you don’t know well, or if your carry involves a knife type that has a history of being regulated, checking the current local law before you carry is the best step.