California Penal Code 21310: Carrying a Concealed Dirk or Dagger

California Penal Code 21310 makes it a crime to carry a concealed dirk or dagger on your person. It’s a wobbler, meaning prosecutors can file it as a misdemeanor carrying up to a year in county jail, or as a felony punishable by 16 months, two, or three years.¹ The prosecution does not need to prove you planned to use the weapon or commit any other crime. Concealment of a qualifying stabbing instrument is the whole offense.

What the Statute Prohibits

The statute targets one thing: carrying a dirk or dagger concealed on your body. Open carry of the same weapon is not covered. If the knife rides in a sheath hanging visibly from your waist, you have not violated PC 21310.²

Certain people are exempt entirely. PC 21310 cross-references the exceptions starting at Penal Code 17700, which cover law enforcement officers, active military personnel, and other authorized individuals.¹

What Counts as a Dirk or Dagger

Penal Code 16470 defines a dirk or dagger as any knife or instrument, with or without a handguard, capable of ready use as a stabbing weapon that could inflict great bodily injury or death.³ The definition is deliberately broad. A screwdriver, an ice pick, or a sharpened piece of metal can qualify. There is no blade-length cutoff. The question is whether the item can be readily used to stab.

Folding knives get a specific carve-out. A nonlocking folding knife or pocketknife only counts as a dirk or dagger if the blade is exposed and locked into position.³ A closed pocketknife in your pocket is not a violation. Open that same knife and lock the blade while it sits inside your jacket, and it is.

What “Concealed” Means

The weapon must be substantially concealed on your person. Complete invisibility is not required. A knife tucked into a waistband under a shirt, slipped inside a boot, or stashed in an inner jacket pocket all meet the concealment threshold.

The one clear safe harbor: a knife carried in a sheath worn openly and suspended from the waist is not considered concealed.² This is where people get tripped up. If the sheath is visible but a long shirt or coat covers the handle, a prosecutor can argue the weapon was still substantially concealed. Keeping the entire sheath and handle visible is the safest practice.

What the Prosecution Must Prove

CALCRIM 2501, the standard jury instruction, sets out four elements the prosecution must prove beyond a reasonable doubt:

You carried a dirk or dagger on your person.
You knew you were carrying it.
The weapon was substantially concealed on your person.
You knew the item could be readily used as a stabbing weapon.

The instruction is explicit that the prosecution does not need to prove you intended to use the dirk or dagger as a weapon.² Utility purposes are no defense. If the item qualifies and you concealed it knowingly, the charge stands.

Penalties

Misdemeanor

A misdemeanor conviction carries up to one year in county jail.¹ Judges often impose summary probation in place of jail, along with fines. It still creates a criminal record that can affect employment and licensing.

Felony

A felony conviction triggers a sentencing triad of 16 months, two years, or three years, served in county jail under the realignment framework in Penal Code 1170(h).⁴ The court may impose formal felony probation with check-ins, search conditions, and a weapons prohibition. Fines can reach $10,000.

Which level the prosecutor picks turns on your criminal history, the type of weapon involved, and whether other criminal activity was going on when you were arrested. A first-time defendant caught with a kitchen knife is more likely to face a misdemeanor than someone with priors carrying a fixed-blade combat knife near a school.

Consequences Beyond Jail

A felony conviction under PC 21310 triggers a lifetime ban on owning or possessing firearms under both state and federal law.⁵ Penal Code 29800 then makes it a separate felony for anyone with a prior felony conviction to possess a firearm.⁶ One PC 21310 felony can snowball into new charges if you later come near a gun.

A felony record also affects employment, professional licensing, housing applications, and jury service. For non-citizens, the stakes climb higher. A felony weapons conviction can trigger deportability under federal immigration law, particularly if the offense is classified as a crime involving moral turpitude or an aggravated felony, and it can block immigration benefits depending on how it is categorized.

Defenses That Fit the Elements

Because the elements are compact, most defenses attack one of the four prongs directly.

You Didn’t Know You Were Carrying It

If you genuinely did not know the item was on your person, the mental-state element fails. This comes up when someone borrows a bag with a knife inside, or a passenger sits in a car where a weapon was left under the seat. Without proof of knowledge, the charge does not survive.

Prosecutors rarely have a confession about what someone knew, so they lean on circumstantial evidence to build the knowledge element. California’s jury instructions set a high bar for that kind of proof: when circumstantial evidence is used to establish a mental state, jurors must be convinced the only reasonable conclusion is that the defendant had the required knowledge. If the evidence supports two reasonable interpretations and one points toward innocence, jurors must adopt the one favoring the defendant.⁷

The Weapon Wasn’t Concealed

If the dirk or dagger was carried openly, PC 21310 does not apply. The sheath-at-the-waist rule is the clearest version.² Even without a sheath, a plainly visible weapon does not meet the concealment element. These disputes are fact-specific and turn on witness testimony and the arresting officer’s account.

The Item Isn’t a Dirk or Dagger

Not every sharp object qualifies. A closed folding knife with the blade retracted does not meet the statutory definition.³ Defense attorneys challenge whether the object was actually capable of ready use as a stabbing weapon. A butter knife or small utility tool may not clear that threshold.

Illegal Search and Seizure

Police often discover concealed weapons during traffic stops, pat-downs, or vehicle searches. If officers lacked probable cause for the stop, or searched without a warrant or a valid exception, a motion to suppress can exclude the weapon from evidence. Without the weapon, the case usually collapses.

Reducing or Cleaning a Conviction

Because PC 21310 is a wobbler, someone convicted of a felony may petition the court to reduce the conviction to a misdemeanor under Penal Code 17(b). This works best for defendants who completed probation and stayed out of trouble. A reduction restores firearms rights under California law, though federal restrictions may still apply, and it removes some collateral consequences of a felony record.

After a reduction, or for a defendant convicted of a misdemeanor from the start, California law allows petitioning to have the conviction dismissed under Penal Code 1203.4. A granted petition withdraws the guilty plea and dismisses the case. It does not erase the record entirely: the conviction still appears in law enforcement background checks, and some professional licensing boards can still consider it. For most employment purposes, though, a dismissed conviction carries meaningfully less weight than an active one.

1
California Legislative Information. California Penal Code 21310
2
Justia. CALCRIM No. 2501 Carrying Concealed Explosive or Dirk or Dagger
3
California Legislative Information. California Penal Code 16470
4
California Legislative Information. California Penal Code 1170(h)
5
California Department of Justice. Firearms Prohibiting Categories
6
California Legislative Information. California Penal Code 29800
7
Justia. CALCRIM No. 225 Circumstantial Evidence – Intent or Mental State