Missouri state knife laws are relatively favorable to today’s knife owner. The state upholds the Missouri citizen’s right to bear bladed arms.
It allows everyone to keep bladed weapons (with some exceptions) and use them in the defense of themselves, their home, and their property, or when summoned (in a legal manner) to render assistance to the “civil power”. According to the state statutes, that right may not be brought into question. However, in the state of Missouri, this part of the law is not a justification for keeping concealed weapons on your person.
Missouri has no laws that forbid owning knives of a particular type or length. Prior to 2012, switchblade knives had been forbidden, but that prohibition has been removed from law. However, there is still a federal law in place regarding switchblades, enacted back in 1958. That law doesn’t forbid carrying or owning a switchblade, but just the manufacture, transport and sales of switchblades in interstate commerce.
Regarding concealed carry (carrying a knife that is not in full view) Missouri law does not allow it. An exception is made only for what is considered a pocketknife that contains a blade whose length is shorter than four inches. So if a citizen wears a concealed knife (other than a common pocketknife) somewhere on his or her body, he or she is committing a crime under Missouri law. Where this part is described in the law, it also mentions that guns or other weapons that could easily be used as a lethal weapon are included in the prohibition.
A knife, according to Missouri statutes, is defined as any “bladed hand instrument” such as a dirk, dagger, or stiletto that can be used to perpetrate severe or lethal injury via slicing or a stab wound. But again, a simple pocketknife with a blade of under four inches is considered separate from that definition, because it is allowed for concealed carry, whereas the other bladed instruments are not.
As to minors, there are no current restrictions in Missouri laws regarding minors owning or carrying knives. There are also no statewide preemptions in Missouri knife laws.
So although state knife laws are reasonably favorable for knife owners living in or visiting Missouri, concealed carry is not allowed. If you normally carry a knife (other than a sub-four-inch pocketknife) it may be wise to choose to leave it behind when you leave your home or keep it visible in a sheath on your belt. Other than that, there are no restrictions, and the Missouri knife laws will be very easy to remember.
This information that is presented as a brief description of the laws and not as any kind of legal advice. aStraightArrow will not and cannot be a legal service provider. The use of the site does not create any sort of client/lawyer relationship. The knife laws are interpreted differently by prosecuting attorneys, enforcement officers, and judges. aStraightArrow suggests you consult legal counsel for further guidance.