I live in California and train Law Enforcement.
The law specifically says "Double edged dirks or daggers", which traditionally have pointed tips (spear point type). I have asked my friends/students if a double edged Busse would be illegal. The answer in court would be NO. However, any cop who wanted to could give you a lot of trouble as it is up to their judgment. It would depend entirely on what you were doing with it.
Laws in California are jacked (hard). One state over its legal to own a chain gun.
It is perfectly legal to own one and to carry openly suspended from waist. Double edged or not. However any type of fixed blade knife is considered a dirk or dagger and cannot be concealed at all.
" 653k: Every person who possesses in the passenger's or driver's area of any motor vehicle in any public place or place open to the public, carries upon his or her person, and every person who sells, offers for sale, exposes for sale, loans, transfers, or gives to any other person a switchblade knife having a blade two or more inches in length is guilty of a misdemeanor.
For the purposes of this section, "switchblade knife" means a knife having the appearance of a pocketknife and includes a spring-blade knife, snap-blade knife, gravity knife or any other similar type knife, the blade or blades of which are two or more inches in length and which can be released automatically by a flick of a button, pressure on the handle, flip of the wrist or other mechanical device, or is released by the weight of the blade or by any type of mechanism whatsoever. "Switchblade knife" does not include a knife that opens with one hand utilizing thumb pressure applied solely to the blade of the knife or a thumb stud attached to the blade, provided that the knife has a detent or other mechanism that provides resistance that must be overcome in opening the blade, or that biases the blade back toward its closed position.
For purposes of this section, "passenger's or driver's area" means that part of a motor vehicle which is designed to carry the driver and passengers, including any interior compartment or space therein."
and
" 12020. (a) Any person in this state who does any of the following is punishable by imprisonment in a county jail not exceeding one year or in the state prison:
(1) Manufactures or causes to be manufactured, imports into the state, keeps for sale, or offers or exposes for sale, or who gives, lends, or possesses...any ballistic knife...any nunchaku...any metal knuckles, any belt buckle knife, any leaded cane, any zip gun, any shuriken [ed: "throwing star"]...any lipstick case knife, any cane sword, any shobi-zue, any air gauge knife, any writing pen knife, any metal military practice handgrenade or metal replica handgrenade, or any instrument or weapon of the kind commonly known as a blackjack, slungshot, billy, sandclub, sap, or sandbag. [Ed. Note: this is the paragraph covering "what you cannot own at all" - some of it is downright weird. Plastic/ceramic knives that can go through a metal detector are also banned somewhere in PC12020.]
...
(4) Carries concealed upon his or her person any dirk or dagger.
...
(24) As used in this section, a "dirk" or "dagger" means a knife or other instrument with or without a handguard that is capable of ready use as a stabbing weapon that may inflict great bodily injury or death. A nonlocking folding knife, a folding knife that is not prohibited by Section 653k, or a pocketknife is capable of ready use as a stabbing weapon that may inflict great bodily injury or death only if the blade of the knife is exposed and locked into position. [Ed. note: so if it's a PC653k-legal knife, and it's carried concealed while folded, it's not "readily available" and therefore doesn't meet the "dirk or dagger definition". ONLY "dirks or daggers" need to be open-carry.]
...
25(d) Knives carried in sheaths which are worn openly suspended from the waist of the wearer are not concealed within the meaning of this section."
On school grounds it gets a bit more strict:
" 626.10. (a) Any person, except a duly appointed peace officer as defined in Chapter 4.5 (commencing with Section 830) of Title 3 of Part 2, a full-time paid peace officer of another state or the federal government who is carrying out official duties while in this state, a person summoned by any officer to assist in making arrests or preserving the peace while the person is actually engaged in assisting any officer, or a member of the military forces of this state or the United States who is engaged in the performance of his or her duties, who brings or possesses any dirk, dagger, ice pick, knife having a blade longer than 21/2 inches, folding knife with a blade that locks into place, a razor with an unguarded blade, a taser, or a stun gun, as defined in subdivision (a) of Section 244.5, any instrument that expels a metallic projectile such as a BB or a pellet, through the force of air pressure, CO2 pressure, or spring action, or any spot marker gun, upon the grounds of, or within, any public or private school providing instruction in kindergarten or any of grades 1 to 12, inclusive, is guilty of a public offense, punishable by imprisonment in a county jail not exceeding one year, or by imprisonment in the state prison. [Ed. Note: This is the paragraph dealing with legal carry on K-12 school grounds. Note that folding lockblades bigger than 2.5" are banned. This applies to any adult on campus; there are exceptions for work-related stuff in part "C" through "G" below.]
(b) Any person, except a duly appointed peace officer as defined in Chapter 4.5 (commencing with Section 830) of Title 3 of Part 2, a full-time paid peace officer of another state or the federal government who is carrying out official duties while in this state, a person summoned by any officer to assist in making arrests or preserving the peace while the person is actually engaged in assisting any officer, or a member of the military forces of this state or the United States who is engaged in the performance of his or her duties, who brings or possesses any dirk, dagger, ice pick, or knife having a fixed blade longer than 21/2 inches upon the grounds of, or within, any private university, the University of California, the California State University, or the California Community Colleges is guilty of a public offense, punishable by imprisonment in a county jail not exceeding one year, or by imprisonment in the state prison. [Ed. Note: This paragraph covers colleges and universities. There is still a ban on large fixed-blades, but large locking folders legal under Penal Code 653k are completely legal. This applies to any adult age 18 or over on campus, student or otherwise; there are exceptions for work-related stuff in part "C" through "G" below.]
(c) Subdivisions (a) and (b) do not apply to any person who brings or possesses a knife having a blade longer than 21/2 inches or a razor with an unguarded blade upon the grounds of, or within, a public or private school providing instruction in kindergarten or any of grades 1 to 12, inclusive, or any private university, state university, or community college at the direction of a faculty member of the private university, state university, or community college, or a certificated or classified employee of the school for use in a private university, state university, community college, or school-sponsored activity or class.
(d) Subdivisions (a) and (b) do not apply to any person who brings or possesses an ice pick, a knife having a blade longer than 21/2 inches, or a razor with an unguarded blade upon the grounds of, or within, a public or private school providing instruction in kindergarten or any of grades 1 to 12, inclusive, or any private university, state university, or community college for a lawful purpose within the scope of the person's employment.
(e) Subdivision (b) does not apply to any person who brings or possesses an ice pick or a knife having a fixed blade longer than 21/2 inches upon the grounds of, or within, any private university, state university, or community college for lawful use in or around a residence or residential facility located upon those grounds or for lawful use in food preparation or consumption.
(f) Subdivision (a) does not apply to any person who brings an instrument that expels a metallic projectile such as a BB or a pellet, through the force of air pressure, CO2 pressure, or spring action, or any spot marker gun upon the grounds of, or within, a public or private school providing instruction in kindergarten or any of grades 1 to 12, inclusive, if the person has the written permission of the school principal or his or her designee.
(g) Any certificated or classified employee or school peace officer of a public or private school providing instruction in kindergarten or any of grades 1 to 12, inclusive, may seize any of the weapons described in subdivision (a), and any certificated or classified employee or school peace officer of any private university, state university, or community college may seize any of the weapons described in subdivision (b), from the possession of any person upon the grounds of, or within, the school if he or she knows, or has reasonable cause to know, the person is prohibited from bringing or possessing the weapon upon the grounds of, or within, the school.
(h) As used in this section, "dirk" or "dagger" means a knife or other instrument with or without a handguard that is capable of ready use as a stabbing weapon that may inflict great bodily injury or death."
