The law in California regarding knives is fairly lenient. The use of a deadly force is an entirely separate subject and should be studied. Knives have long been used in sportsmanship such as hunting and fishing, as a tool in the pocket and as a mean of protection.

Section 12020

Section 12020 holds all persons in violation of carrying knives, dirk/daggers, switchblades, brass knuckles and basically any other weapon with a pointy tip and does not close up to a year in county jail or state prison.

Sales & Possesion

If you manufacture, import, obtain for sale, offers or expose for sale, lend, or posses any of the classified knives in section 12020, the punishment is up to a year in county jail or state prison.

Section 626.10: Schools

In grades K through 12th, no knife of any kind is legal with the exception of study-related types (i.e., kitchen knife in cooking class). At universities and colleges, fixed blades over 2.5 inches are banned. Other folding knives that are not switchblades under Penal Code 653k are permitted.

Section 653k

Lockable folding knives must have some sort of push device--whether a thumbstub, disk,or other device--attached directly to the blade. They must not have a spring design that handles all of the knife's openings. The blade needs to stay closed or have the tendency to stay closed. If the knife posses these qualities, it is not defined as a "switchable" or a "gravity" knife, which are illegal. Knives not classified as a "switchable" or "gravity" can be carried concealed as long as they are closed.

Violation of the Law

If you find yourself faced with law enforcement, do not check to see if your weapon is still concealed. If you find yourself in a situation where blood has been drawn, do not talk, tell the enforcement officer you are too upset to talk or ask for a lawyer.

Source:

Keg Lawyers: Blog-What Constitutes Dangerous Weapons

California Law: A Comprehensive Guide

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