Butterfly knives, also called "Balisong knives," are considered to have a dangerous nature and speedy deployment features, and in consequence they are illegal in many countries. Certain Balisong knife trainers feature blunt blades and are sometimes deemed legal in countries where regular butterfly knives are outlawed.
According to The Art of the Butterfly Knife, the knife is not illegal in all U.S. states. In certain jurisdictions, the knives are classified as gravity knives, switchblades or daggers. In California, the knives are illegal if the blades are longer than two inches. Texas classifies butterfly knives as switchblades and prohibits not only possession, but also the manufacture, transport and sale of these knives. It is not illegal for a person to have a butterfly knife in Utah as long as the knife is not concealed.