In an era where virtually everything is a crime, it is important to know the law. This is especially true with regard to knife laws which vary tremendously. They not only vary state to state but from municipality to municipality as there are few state preemption laws with regard to knifes.
The infographic below from Knifeup.com is a good start and presents the info in an easily understood form. I’d also suggest becoming a member of Knife Rights as they are taking the fight for knife rights to both the court house and the state house.
One example of how fast knife laws are changing is the info below on which states make automatic or switchblade knives illegal. It lists both Kansas and Missouri as prohibiting them. Thanks to Knife Rights, this was recently changed and they are now legal there.
Infographic removed due to inaccuracies.
H/T Liston Matthews of Good Hill Press