Penal Code § 21510 PC – Possession of a Switchblade (2024)

Penal Code § 21510 PC prohibits you from carrying, possessing in public, selling or giving away a switchblade. Doing so is a misdemeanor punishable by probation, fines of up to $1000.00, and up to 6 months in county jail.

California Penal Code Section 17235 provides the legal definition of a switchblade: a pocketknife with a blade of 2 or more inches that can be released by

• a flick of a button,
• pressure on the handle,
• a flip of the wrist, or
• another mechanical device.

Specifically, if a switchblade has a blade two inches or more in length, it is a crime to:

• Possess the knife in the passenger’s or driver’s area of any motor vehicle in any public place or place open to the public,
• Carry the switchblade upon your person, or
• Sell, offer or expose for sale, or loan, transfer, or give the knife to anyone else.¹

Unlike some other knives, which may be carried on your person if closed or if openly worn, switchblades may not be carried at all – even if the blade is not exposed.² In other words, there is no “open-carry” exception to the switchblade laws.

If you carry a switchblade concealed on your person, you could be charged instead with a violation of Penal Code 21310, which prohibits carrying a concealed “dirk” or “dagger.”³ If you are convicted of carrying a concealed dirk or dagger, you could face up to 3 years in state prison.

Legal defenses

Fortunately, there are a number of potential legal defenses that can help you successfully fight California switchblade charges.

These include (but are not limited to):

• Your knife does not meet the legal definition of a switchblade;
• You did not know or realize you were carrying a switchblade on your person;
• Someone else had your switchblade, but you did not give it to them;
• The weapon was discovered during an illegal search and seizure; and/or
• Police misconduct.

To help you better understand the laws relating to possession of a switchblade, our California criminal defense lawyers will explainthe following:

• 1. How does California law define a switchblade?
• 2. What is prohibited under Penal Code 21510 PC?
• 3. What does it mean “knowingly” to carrya switchblade?
• 4. What can a defense attorney do to fight the charges?
• 5. What is the punishment if I am convicted?
• 6. Related California knife laws
  • 6.1. “Dirks” and “daggers” – Penal Code 16470 and 21310
  • 6.2. California’s “open-carry” law for dirks and daggers – Penal Code 20200
  • 6.3. Prohibited knives
  • 6.4. Special restrictions on knives in public buildings and schools – Penal Code 171b and 626.1
• 7. Federal switchblade law 15 USC 1241 – 44 and 18 USC 1716
• 8. Background to current switchblade laws

If, after reading this article, you would like more information, we invite you to contact us at Shouse Law Group.

1.How does California law define a switchblade?

Under Penal Code 17235, a “switchblade knife” is defined as a knife that:

1. has the appearance of a pocketknife, and
2. has a blade, or blades, two or more inches in length, which can be released automatically by:
   • a flick of a button,
   • pressure on the handle,
   • a flip of the wrist, or
   • another mechanical device,

or which is/are released by the weight of the blade(s) or by any type of mechanism whatsoever. ⁴⁵

A switchblade is sometimes referred to as an

• automatic knife,
• pushbutton knife,
• ejector knife,
• switch knife,
• Sprenger or Springer knife, or
• flick knife.

Illegal switchblades under Penal Code 17235 PC also include

• pring-blade knives,
• snap-blade knives,
• gravity knives and
• similar knives

Other knives that fall within the definition of switchblade include “balisong” or “batanga” knives, also called “butterfly” or “fan” knives.⁶ These are folding pocket knives with two handles that counter-rotate around the tang. When closed, the blade is concealed within grooves in the handles.

Ballistic knives are a special type of spring-loaded knife, and are covered under Penal Code 16220 and Penal Code 21110.⁷ Possession of a ballistic knife is punishable by up to one (1) year in county jail.

Exception:

Under Penal Code 17235, “switchblade knife” does not include any knife that opens with one hand utilizing either:

• 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.

A detent is a device – such as a catch, dog, or spring-operated ball – for positioning and holding one mechanical part in relation to another, in a manner such that the device can be released by force applied to one of the parts.⁸

Thus, most utility knives and folding pocket knives, regardless of length, are not switchblades under Penal Code 17235 as long as there is some mechanism that provides resistance to opening the knife.

However, it is still illegal to carry concealed utility or pocket knives if the blade is

• exposed and
• locked into position.⁹

2.What is prohibited under Penal Code 21510 PC?

Penal Code 21510 PC¹⁰ makes it illegal to do any of the following:

• possesses a switchblade in the passenger’s or driver’s area of a motor vehicle in a public place, or any place open to the public;
• carry a switchblade on your person;
• sell, offer for sale, or expose a switchblade for sale; or
• loan, transfer, or give a switchblade to any other person.¹¹

The “passenger’s or driver’s area” is the part of a motor vehicle designed to carry the driver and passengers, including any interior compartment or space therein.¹²

3.What does it mean “knowingly” to carry a switchblade?

Before you can be convicted for violating Penal Code 21510 PC, the prosecutor must prove that:

1. you knew you had a switchblade on your person or in your vehicle, AND
2. you knew it had the characteristics of a switchblade.¹³

The prosecutor does not need to prove that you used – or intended to use – the switchblade as a weapon.¹⁴ If you knowingly have a switchblade on your person – or in the interior cabin of a motor vehicle – you violate Penal Code 21510, even if you had no intention of using it as a weapon.

Note that you do not need actually to hold or touch a switchblade in order to possess it. It is enough for you to have

• control over the switchblade, or
• the right to control it,

either personally or through another person.¹⁵

Thus having a switchblade in your jacket pocket or purse would count as carrying it on your person.

Example: When Jane’s grandfather died, he left her a small butterfly knife, with a 3″ blade, which he got in the Philippines during World War II. She keeps it with her at all times as a keepsake reminder of him.

Jane has no interest in using the knife as a weapon. In fact, because it opens so easily, she keeps the handles tied shut with a ribbon.

Jane is arrested one night on suspicion of a DUI, and the knife is found in her purse. Even though Jane never had any intention of using the knife as a weapon, she gets charged with the crime of possession of a switchblade. This is because she knows that her purse contains a knife that opens with no resistance and has a blade at least 2″ long.

4.What can a defense attorney do to fight the charges?

Fortunately, there are a number of legal defenses that a good criminal defense lawyer can present on your behalf. These might include.

Your knife does not meet the legal definition of a switchblade

The definition of a switchblade under Penal Code 21510 PC is very specific. Usually it will be easy to tell whether your knife meets the legal definition.

Sometimes, however, people with legal folding knives are accused of carrying switchblades. This might happen if the arresting officer or a prosecutor is able to open your knife one-handed with a sharp flick of their wrist, despite the presence of a detent.

Just because you, a police officer or a prosecutor can open your knife with a wrist flick, that does not automatically qualify the knife as a switchblade. As long as the knife has

• a working thumb stud or
• other mechanisms which make it resistant to being opened,

it is not legally a switchblade under California law¹⁶.

You did not know that you were carrying a switchblade

• If you did not know that you were carrying a knife (switchblade or otherwise), OR
• If you knew you were carrying a knife, but you did not know it had the characteristics of a switchblade,

then you are not liable for a crime.

Example: You are caught with a switchblade tucked into the waistband of your jeans. Since the weapon is right next to your body, a prosecutor will most likely be able to prove you knew you had a switchblade on your person.

Example: Though if the switchblade was in the pocket of a jacket that you borrowed from a friend, it might be difficult for the prosecutor to prove that 1) you knew it was there, or 2) that if you knew it was there, that you knew it had the characteristics of a switchblade.

5. What is the punishment if I am convicted?

Violation of Penal Code 21510 PC is a misdemeanor under California law, that can be punished by as much as:

• up to six months in county jail, and/or
• a fine of up to $1,000.

Often, however, California misdemeanor violations are punished by misdemeanor (summary) probation with little or no jail time.

A judge may be more likely to sentence you to jail time and/or a fine if they find aggravating factors that may include (but are not limited to):

• a prior criminal record,
• gang ties,
• a history of violence,
• a finding that you intended to use the switchblade as a weapon; and/or
• a lack of cooperation with the police during your arrest.

If you are sentenced to summary probation, the judge will impose a number of conditions. You must adhere to these conditions in order to avoid going to jail or returning to jail.

These can include (but are not limited to):

• community service or labor (such as CAL-TRANS roadside work),
• electronic monitoring or house arrest,
• participation in counseling / treatment programs, and/or
• paying victim restitution.

6. Related California knife laws

In California it is legal to carry some but not all other types of knives on your person if they are openly worn.

6.1. “Dirks” and “daggers” – Penal Code 16470 and 21310

Penal Code 21310 PC makes it a crime to carry a concealed “dirk” or “dagger” upon your person.

A dirk or a dagger is defined in Penal Code 16470 PC as:

1. a knife or other instrument,
2. with or without a handguard,
3. that is capable of ready use as a stabbing weapon, and
4. that may inflict great bodily injury or death.¹⁷

California law defines “great bodily injury” to mean a significant or substantial physical injury.¹⁸

The following are considered 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:

• pocket knives,
• non-locking folding knives, and
• other folding knives that do not meet the definition of a switchblade.¹⁹

Legal defenses to carrying a concealed dirk or dagger

In addition to the general legal defenses set out above, other defenses to carrying a concealed dirk or dagger may include:

• You were carrying a folding knife, but the blade was not exposed;
• You were carrying an open folding knife, but the blade was not locked into position;
• The knife you were carrying was not a dirk or dagger because its characteristics substantially limited its effectiveness as a stabbing weapon (for example, a bread knife with a dull edge, a serrated edge and a rounded end).²⁰

Penalty for carrying a concealed dirk or dagger in California

Under Penal Code 21310 PC, carrying a concealed dirk or dagger is a wobbler, meaning it could be filed as a misdemeanor or a felony.

As a misdemeanor, carrying a concealed dirk or dagger carries possible penalties of:

• up to one-year county jail, and/or
• up to a $1,000 fine.

As a felony, it carries:

• 16 months, or two or three years in county jail, and/or
• up to a $10,000 fine.²¹

6.2. California’s “open-carry” law for dirks and daggers

Under Penal Code 20200 – California’s “open-carry” knife law – you may carry a dirk or dagger on your person as long as it is:

1. carried in a sheath, and
2. the sheath is worn openly suspended from your waist.²²

Folding knives that do not meet the legal definition of a switchblade may also be concealed on your person, as long as they are carried in the folded position.

6.3 Prohibited knives

California completely prohibits the possession, sale, manufacture or import of certain other types of knives, including:

• air gauge knives [items that appear to be air gauges, but are actually knives],²³
• ballistic knives,²⁴
• belt buckle knives,²⁵
• cane swords,²⁶
• undetectable knives [made from materials that cannot be detected by metal detectors],²⁷
• lipstick case knives,²⁸
• shobi-zues [also called shinobi-zues] (staffs, crutches, sticks, rods, or poles concealing a knife or blade which may be exposed by a flip of the wrist or by a mechanical action),²⁹ and
• writing pen knives.³⁰

Possession, sale, manufacture or import of an undetectable knife is a misdemeanor.

Possession, sale, manufacture or import of any other prohibited knife is a wobbler.

Misdemeanor penalties include

• up to 1-year county jail and/or
• up to a $1,000 fine.

Felony penalties include

• up to 3 years in county jail and/or
• up to a $10,000 fine.

6.4 Special restrictions on knives in public buildings and schools – Penal Code 171b and 626.10

Penal Code 171b PC makes it a crime to bring or possess within any state or local public building – or at any meeting required to be open to the public – any of the following:

1. a switchblade,
2. any knife having a blade in excess of four inches which is fixed – or is capable of being fixed – in an unguarded position by the use of one or two hands, or
3. certain types of knives considered to be “generally prohibited weapons,” including:
   • air gauge knives,
   • ballistic knives,
   • belt buckle knives,
   • cane swords,
   • lipstick case knives,
   • shobi-zues, and
   • writing pen knives.³¹

Violations of Penal Code 171b are punishable by

• up to one year in county jail as a misdemeanor, or
• up to 3 years in California state prison as a felony.

Penal Code 626.10(a)(1) PC makes it illegal to bring any of the following onto a public or private school instructing children in grades kindergarten to 12:

• a dirk or dagger,
• an ice pick,
• a knife having a blade longer than 2^1/2“,
• a folding knife with a blade that locks into place, or
• a razor with an unguarded blade.³²

Violation of Penal Code 626.10 is punishable by up to one (1) year in county jail.

7. Federal switchblade law – 15 USC 1241 – 44 & 18 USC 1716

Generally, California criminal laws apply exclusively to crimes committed in California. Exceptions are crimes committed on some federally owned properties, such as:

• federal parks,
• military installations,
• lands administered by Indian tribes,
• Veteran’s Administration facilities,
• federal prisons,
• United States postal facilities,
• federal courts, and
• airports.³³

The federal switchblade statute is set forth in 15 USC 1241 – 44.

It defines a “switchblade knife” as any knife having a blade which opens automatically by either:

• hand pressure applied to a button or other device in the handle of the knife, or
• operation of inertia, gravity, or both.³⁴

Under the federal switchblade law, it is a crime to:

• introduce or transport a switchblade in interstate commerce, ³⁵ or
• possess a switchblade on federal or Indian lands, or lands subject to federal jurisdiction; ³⁶

unless

• you are a member of the armed forces acting in the performance of your duty, or
• you have only one arm and the blade is three inches or less in length. ³⁷

“Interstate commerce” means commerce between any State, Territory, possession of the United States, or the District of Columbia, and any place outside thereof.³⁸

Penalties for violation of federal switchblade laws are:

1. a fine of not more than $2,000, and/or
2. imprisonment of not more than five years.

In addition, 18 USC 1716(g) makes it a crime to mail a switchblade or ballistic knife via U.S. mail.

Penalties for mailing a switchblade or ballistic knife include:

• a fine of up to $5,000 or more, and/or
• imprisonment of not more than one (1) year.³⁹

8. Background to current switchblade laws

California and federal laws making it a crime to carry a concealed switchblade were first enacted in 1957 and 1958, respectively. At the time, movies like West Side Story and Rebel Without a Cause were popularizing the image of a young delinquent with a switchblade or flick knife.

Over time the definitions of “switchblade knife” were expanded, to the point where it was arguably a crime for law-abiding citizens to carry knives for legitimate purposes.

In response to such concerns, a 1996 amendment to California’s switchblade law – then Penal Code 653k – exempted from the definition of “switchblade knife” all knives designed to be opened with one hand via pressure on a thumb-stud or hole in the blade.

The Senate Committee on Criminal Procedure for the 1995-96 regular session noted that the amendment was needed because:

“Such knives are routinely used for hunting, fishing, climbing or any other activity where a knife is necessary, but two handed use is not possible or desirable. Owners of such knives should not be subject to potential arbitrary enforcement of the overly broad language currently contained in Section 653k.”⁴⁰

But according to the California District Attorneys Association, the 1996 amendment:

“created an unintended loophole for criminals to carry dangerous weapons. After passage of the new law, law enforcement began finding imported knives possessed by criminals which appeared to meet the technical language of the exemption; namely switchblade knifes equipped with thumb studs which served no real purpose. As a result, law enforcement or the courts have been compelled to return these dangerous weapons.”⁴¹

To plug up this hole, in 2001, then-state Senator Betty Karnette introduced California SB 274. It proposed modifying Penal Code 653k by adding language stating that to be exempt from the definition of a switchblade, a knife must have a detent or mechanism giving the knife a “bias toward closure.”

Writing in support of SB 274, the American Knife and Tool Institute wrote:

“The exception for one-handed opening knives was designed to decriminalize the legitimate use of these extremely functional tools by law-abiding citizens. The proposed amendments accomplish this important purpose by establishing more objective criteria for determining whether a knife meets the intended exception to the switchblade law.”⁴²

Questions over the scope of the proposed amendment remained, however.

To clarify the legislative intent behind the proposed amendment, Senator Karnette wrote a letter, dated July 18, 2001, which was read into the Senate’s official record. It said, in part:

“In order to ensure that only legitimate one-handed opening knives are covered, SB 274 narrows the language to only allow knives to fall under the exemption from the switchblade law if that one-handed opening knife contains a detent or similar mechanism. Such mechanisms ensure there is a measure of resistance (no matter how slight) that prevents the knife from being easily opened with a flick of the wrist. Moreover, a detent or similar mechanism is prudent and a matter of public safety as it will ensure that a blade will not inadvertently come open.

Although some one-handed opening knives can be opened with a strong flick of the wrist, so long as they contain a detent or similar mechanism that provides some resistance to opening the knife, then the exemption is triggered. These knives serve an important utility to many knife users, as well as firefighters, EMT personnel, hunters, fishermen, and others.”⁴³

SB 274 was signed into law by then-Governor Gray Davis signed in 2001.

A similar concern was addressed in the 2009 amendment to the Switchblade Knife Act of 1958, 15 U.S.C.1241- 45.

That amendment also added language exempting from the definition of switchblade knives containing a detent or other mechanism giving the knife a bias toward closure.⁴⁴

The federal change was made after intense lobbying efforts by knife owners, retailers and manufacturers, who were concerned that prior restrictions on switchblade possession were making pocket knives – as well as work and hunting knives – illegal.

For further help…

If you or a loved one is charged with Penal Code 17235 PC & 21510 PC carrying a switchblade and you are looking to hire a criminal defense attorney for representation, we invite you to contact us at Shouse Law Group. We can provide a consultation in the office or by phone.

We have local offices in Los Angeles, the San Fernando Valley, Pasadena, Long Beach, Orange County, Ventura, San Bernardino, Rancho Cucamonga, Riverside, San Diego, Sacramento, Oakland, San Francisco, San Jose and throughout California. For information on Nevada switchblade laws, see our article on Nevada switchblade laws. For Colorado cases, see our page on “possession of a switchblade” laws in Colorado.

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