California has some of the most detailed knife laws in the country, and one of the most important statutes to understand is Penal Code § 17235 PC, which defines what the state legally considers a switchblade knife. Knowing this definition is crucial for anyone who owns, carries, sells, or collects knives in California because it determines whether a particular knife is legal or restricted under state law.
This comprehensive guide explains the legal definition of a switchblade, the knives that are included and excluded, how this law connects to other penal code sections, and what practical steps you should take to stay compliant.
The Legal Definition of a Switchblade in California
Under California Penal Code § 17235, a switchblade knife is defined as any knife that looks like a pocketknife but has a blade or blades two inches or longer that can be released automatically by one of the following actions:
-
Pressing a button
-
Applying pressure on the handle
-
Flipping the wrist
-
Allowing the blade to fall open by gravity or mechanical force
Essentially, if the blade opens automatically or semi-automatically with little to no manual effort, and the blade measures at least two inches, the knife qualifies as a switchblade under California law.
The statute also clarifies that not all folding knives are switchblades. A knife is not considered a switchblade if:
-
It opens with one hand using thumb pressure applied directly to the blade or a thumb stud attached to the blade, and
-
The knife includes a detent or mechanism that provides resistance to opening, or biases the blade closed.
This exclusion is important because it means many everyday folding knives, such as those used for utility or work purposes, are not considered switchblades as long as they require deliberate manual effort to open.
Why the Definition Matters
Understanding this definition is more than a technicality—it determines whether your knife can legally be carried, transported, or sold. The definition in § 17235 is referenced in Penal Code § 21510, which makes it a misdemeanor to:
-
Carry a switchblade on your person
-
Possess a switchblade in a vehicle in a public place
-
Sell, offer to sell, loan, or give a switchblade to another person
This means that once a knife meets the definition outlined in § 17235, it becomes subject to these strict possession and transportation rules. Even if your intent is not to use the knife as a weapon, simply having it on you or in your car could result in criminal penalties.
Knives That Qualify as Switchblades
Certain types of knives almost always fall under the switchblade definition because of their design or operation. These include:
-
Spring-blade knives: Knives that use a spring mechanism to automatically open when a button or lever is pressed.
-
Snap-blade knives: Folding knives that deploy instantly through mechanical assistance.
-
Gravity knives: Knives that open by the weight of the blade or a quick motion of the wrist.
-
Butterfly or balisong knives: Folding knives that can be opened rapidly with a flipping motion, often classified as switchblades if their blade length and mechanism meet the legal definition.
If a knife looks like a pocketknife, has a blade of two inches or longer, and opens automatically or by gravity, it is almost certainly considered a switchblade in California.
Knives That Are Excluded from the Definition
The law provides an explicit exclusion for certain one-hand opening knives. These are typically manual folding knives that require deliberate effort to open and have mechanisms that resist automatic deployment.
For example:
-
A folding knife with a thumb stud that requires applied pressure to the blade.
-
A knife that has a bias-toward-closure design, meaning it naturally stays closed until you deliberately open it.
-
Knives with blades shorter than two inches, which fall outside the switchblade definition altogether.
However, while these knives may not qualify as “switchblades,” they are still subject to other California knife laws. For instance, local ordinances or concealed carry restrictions may still apply.
Practical Implications for Knife Owners in California
Understanding Penal Code § 17235 is essential for anyone who owns or carries knives. Here are the key takeaways every California resident should know:
Carrying a switchblade in public is illegal.
Even if you bought it legally, once you carry it on your person or have it in a vehicle’s passenger area, it can be considered unlawful possession.
Ownership versus carrying.
You can generally own a switchblade and keep it at home or in a private collection, but carrying it in public or in a vehicle can lead to criminal charges under Penal Code § 21510.
Vehicle possession rules.
Keeping a switchblade in the glove compartment, center console, or anywhere within reach in a vehicle that’s in a public place can be treated as the same as carrying it.
Intent doesn’t matter.
California law doesn’t require the prosecution to prove you intended to use the knife as a weapon. Simply possessing or carrying one in violation of the statute is enough for a misdemeanor charge.
Penalties.
Violating switchblade laws can result in fines, probation, or up to six months in county jail.
Blade length matters.
If your knife’s blade is less than two inches long, it’s not a switchblade under § 17235, though local restrictions could still apply.
Local laws may differ.
Cities like San Francisco and Los Angeles have additional knife ordinances, some of which are stricter than state law. Always check your city or county’s municipal code before carrying a knife.
Interpretation and Enforcement
While § 17235 provides a clear definition, its enforcement can vary depending on the knife’s design and how it operates in practice. Law enforcement officers often look at:
-
The knife’s appearance (does it resemble a pocketknife?).
-
The blade’s length (two inches or longer).
-
How the blade opens (mechanical button, gravity, or wrist action).
For example, a butterfly knife or gravity knife that deploys quickly by flicking the wrist is usually treated as a switchblade. Meanwhile, a folding knife with resistance in its hinge and requiring deliberate thumb pressure is typically considered legal.
Even though the distinction may seem small, it can have major consequences. Misunderstanding the mechanics of your knife can easily lead to a citation or arrest if the officer believes it meets the switchblade definition.
Staying Compliant with California Knife Laws
To stay on the right side of California’s switchblade laws, follow these guidelines:
-
Check the mechanism. Ensure your knife does not open automatically by a button, switch, or gravity.
-
Measure the blade. If it’s two inches or longer, automatic opening may put it in the switchblade category.
-
Avoid carrying in public. Even if you legally own a switchblade, carrying it in your pocket or vehicle is risky.
-
Know your local rules. Some municipalities have complete bans on switchblades regardless of blade length.
-
When in doubt, don’t carry it. If you’re unsure whether your knife qualifies as a switchblade, err on the side of caution.
-
Consult an attorney. If you’re facing charges related to knife possession, get legal advice immediately.
Frequently Asked Questions
Can I own a switchblade in California?
Yes, ownership itself is generally not illegal as long as the knife stays in your home or private collection.
Can I carry a small automatic knife?
If the blade is under two inches, it may not meet the switchblade definition, but always check local regulations before carrying it in public.
Are butterfly knives legal?
Butterfly or balisong knives are often treated as switchblades if their blade length is two inches or longer and they open automatically or by wrist motion.
Do I need intent to be charged?
No. Simply carrying or possessing a switchblade in a prohibited area is enough for a misdemeanor charge.
Key Takeaway
California Penal Code § 17235 PC draws a sharp line between ordinary folding knives and restricted switchblades. The main factors are blade length (two inches or longer) and automatic opening mechanism. If both apply, the knife qualifies as a switchblade and is heavily restricted under state law.
If you collect, carry, or use knives in California, understanding this law can save you from legal trouble. The difference between a lawful pocketknife and an illegal switchblade often comes down to a few small details about how the knife opens and how long the blade is.
Need Legal Help? Contact Southwest Legal
If you’ve been charged with possession or carrying a switchblade under California Penal Code § 17235 or §21510, don’t face the situation alone. The consequences can be serious, but a skilled defense attorney can help you protect your rights and your record. Contact us today for a free, confidential consultation with an experienced Southern California criminal defense lawyer. Our team at Southwest Legal will review your case, explain your options, and help you build the strongest defense possible.
