Updated October 2026 | The Bulldog Law | California Criminal Defense

An accomplice is a person who knowingly and intentionally helps or encourages someone else's crime before or during its commission. In California that person is a principal under Penal Code 31, guilty of the crime itself and subject to its full sentence, whether they pulled the trigger, drove the car, or stood watch. An accessory, in California usage, means an accessory after the fact under Penal Code 32: someone who, after the crime is done, knowingly helps the perpetrator avoid arrest, trial, or punishment, and who commits a separate and lesser offense, a wobbler punishable by up to three years. The difference between the two is timing and knowledge, and it is the difference between facing a robbery sentence and facing a maximum of three years. Mere presence at a crime, knowledge without participation, and help given without knowing a crime was involved make a person neither.

The Bulldog Law's attorneys defend a large number of clients whose charge rests on what someone else did: the driver, the lookout, the friend who lent a phone or a car, the roommate who let a person stay after the fact, the co-defendant named by a cooperating witness. The prosecution's theory in those cases is accomplice liability, and the defense is built on its elements. What follows is the definition of each role, the elements the prosecution must prove, a comparison of accomplice, accessory, and conspirator, the special rules for murder after the 2019 reforms, and the defenses. Call (888) 928-1609 or message our team.

California has only two roles: principal and accessory after the fact

The common law divided participants into principals in the first degree (who committed the act), principals in the second degree (who were present and aided), accessories before the fact (who helped but were absent), and accessories after the fact. California abolished the first three distinctions in 1872. Penal Code 31 provides that all persons concerned in the commission of a crime, whether they directly commit the act or aid and abet in its commission, or, not being present, have advised and encouraged it, are principals in any crime so committed. The statute adds people who use a child, a person with a disability, or an intoxicated person to commit a crime, and people who use threats, fraud, or force to make another commit one. Every one of them is a principal, charged with the crime and sentenced for it. The only separate role left is the accessory under Penal Code 32, who helps afterward and is guilty of a different crime. Cornell's Legal Information Institute summarizes the general-law terms, and our page on principals and accessories covers the classification history.

What makes someone an accomplice: aiding and abetting

A person who did not personally commit the act is a principal under Penal Code 31 only if the prosecution proves aiding and abetting, which has three elements. First, the person knew the perpetrator intended to commit the crime. Second, the person intended to aid, facilitate, promote, encourage, or instigate the commission of that crime. Third, the person's words or conduct did in fact aid, encourage, or instigate it. Each element must exist before or during the crime. The knowledge element is specific: the aider must know the particular unlawful purpose, not merely that something illegal might be going on. The intent element requires a purpose to help the crime succeed, not simply a decision to go along. And the act element can be small, driving, keeping watch, providing a tool, giving directions, or encouragement, but it must be something; presence alone, even presence with knowledge, is not aiding and abetting, and neither is failing to stop a crime, except for a person with a legal duty to act. Our page on aiding and abetting under Penal Code 31 covers the elements and the jury instruction in depth. A person who is an aider and abettor is guilty of the crime they intended to aid and, for crimes other than murder, of any other crime that was a natural and probable consequence of it, a doctrine discussed below.

Accomplice, accessory, conspirator, and bystander

Four roles are regularly confused, and the table separates them by the statute, the timing, what the prosecution must prove, and what the person faces.

Conspiracy differs from accomplice liability in that it punishes the agreement itself, so a conspirator can be guilty even if the target crime was never completed, and it requires no act of assistance beyond an overt step by any member. Our pages on criminal conspiracy and Penal Code 182 cover the elements. In practice a prosecutor often charges all three theories, the completed crime as an aider and abettor, conspiracy to commit it, and in the alternative accessory after the fact, and the defense works each one separately.

Accessory after the fact: Penal Code 32

The accessory statute reaches a person who, after a felony has been committed, harbors, conceals, or aids a principal in that felony, with knowledge that the principal committed, was charged with, or was convicted of it, and with the intent that the principal avoid or escape arrest, trial, conviction, or punishment. Both the knowledge and the specific intent are required. The typical accessory is the person who hides a suspect, drives them out of the area, disposes of a weapon or clothing, lies to police about their whereabouts, or provides money to flee, knowing what they did.

A person who helps a friend without knowing about the felony is not an accessory; a person who learns of it afterward and does nothing is not either, because the statute requires affirmative aid. Penal Code 33 sets the punishment as a wobbler: up to one year in county jail, or 16 months, two, or three years. There is no accessory liability for a misdemeanor. The offense is also the common negotiated resolution for a client originally charged as an aider and abettor where the evidence of advance knowledge is weak, because it carries a fraction of the exposure. Our page on accessory after the fact covers the charge in detail.

The special rules for murder

Until 2019, an accomplice could be convicted of murder on two theories that required no intent to kill. Under the natural and probable consequences doctrine, an aider and abettor of a lesser crime, an assault, a burglary, a fight, was guilty of a murder committed by the perpetrator if a reasonable person would have foreseen it. Under the felony-murder rule, every participant in a listed felony was guilty of murder for any death during it. Senate Bill 1437 changed both. Penal Code 188(a)(3) now provides that malice may not be imputed to a person based solely on participation in a crime, which ends the natural and probable consequences theory for murder, and Penal Code 189(e) limits felony murder for a non-killer to a person who intended to kill, or who was a major participant in the felony and acted with reckless indifference to human life. T

he natural and probable consequences doctrine still applies to crimes other than murder, so an aider of an assault remains liable for a foreseeable mayhem or a foreseeable robbery, but the gap between helping and a life sentence has narrowed. People convicted under the old theories may petition for resentencing under Penal Code 1172.6, and our attorneys have handled those petitions since the law took effect. The federal rules differ, and our page on felony murder under federal law covers them; federal accomplice liability generally runs under 18 U.S.C. 2, which treats aiders as principals, and 18 U.S.C. 3, the accessory statute, as our federal charges page explains.

Defenses

Accomplice cases are defended on the elements and on the evidence. Lack of knowledge is the central defense: a client who did not know the perpetrator's purpose cannot have intended to aid it, and the prosecution's evidence of knowledge is usually circumstantial, drawn from the relationship, the planning, the client's conduct before and after, and statements. Lack of intent follows, for a client who knew something was planned but did not share the purpose, and mere presence, for a client who was simply there. Withdrawal is a complete defense to aiding and abetting if, before the crime was committed, the client notified the others that they were no longer participating and did everything reasonably within their power to prevent the crime; withdrawal after the crime is complete is no defense, but it may reduce the client's role to accessory after the fact at most. The scope of the aiding matters: a client who aided one crime is not liable for a different, non-foreseeable crime the perpetrator chose to commit.

And the evidence is attacked: most accomplice cases depend on the testimony of a cooperating co-defendant who has been promised leniency, and Penal Code 1111 bars a conviction on that testimony unless it is corroborated by independent evidence connecting the defendant to the crime, with the jury instructed to view the accomplice's testimony with caution. In the negotiated resolution, the distance between a Penal Code 31 principal charge and a Penal Code 32 accessory plea is the distance between the full sentence for the crime and a maximum of three years, and it is the outcome our attorneys pursue in many cases where the client's involvement came late or was unknowing.

Frequently asked questions

What is an accomplice?

An accomplice is a person who knowingly and intentionally helps, encourages, or facilitates another person's crime, before or during its commission, and who is therefore criminally liable for that crime. In California the statute is Penal Code 31, which treats everyone "concerned in the commission" of a crime as a principal, whether they committed the act themselves or aided and abetted it. An accomplice is punished for the crime itself, exactly as the person who physically committed it.

What is the difference between an accomplice and an accessory?

Timing and liability. An accomplice helps before or during the crime and is a principal under Penal Code 31, liable for the full offense. An accessory, in California, means an accessory after the fact under Penal Code 32: a person who, after the crime is complete, knowingly harbors, conceals, or aids the perpetrator to help them escape arrest, trial, or punishment. The accessory is guilty of a separate and lesser offense, a wobbler punishable by up to three years, not of the underlying crime. California abolished the old common-law categories of principal in the first and second degree and accessory before the fact; everyone who helps before or during is simply a principal.

Can you be charged as an accomplice if you did not know a crime was being committed?

No. Aiding and abetting in California requires that the person knew the perpetrator's unlawful purpose, intended to assist or encourage it, and did something, by act or advice, that aided it. A person who drove a friend somewhere without knowing a robbery was planned, lent a car without knowing its use, or was simply present when a crime occurred is not an accomplice. Mere presence, knowledge without intent to help, and failure to prevent a crime are not enough, though they can be evidence of intent when combined with other facts.

What is the penalty for being an accomplice in California?

The same as for the crime itself. Because Penal Code 31 makes an aider and abettor a principal, the accomplice faces the full range for the offense, including enhancements that apply to the crime and any strike consequences. The accomplice to a robbery faces the robbery sentence; the accomplice to a burglary faces the burglary sentence. Only an accessory after the fact under Penal Code 32 faces a separate, lesser punishment: up to one year in county jail as a misdemeanor, or 16 months, two, or three years as a felony.

Can an accomplice be convicted of murder?

Yes, but the rules changed in 2019. An accomplice who intended to kill or who knowingly aided a killing is guilty of murder. Before Senate Bill 1437, an accomplice could also be convicted of murder under the natural and probable consequences doctrine, for a killing that was a foreseeable result of a lesser crime they aided, and under the felony-murder rule for any death during a felony. Penal Code 188 now bars the natural and probable consequences theory for murder, and Penal Code 189 limits felony murder for non-killers to those who were major participants acting with reckless indifference to human life. People convicted under the old rules can petition for resentencing under Penal Code 1172.6.

Can someone be convicted on an accomplice's testimony alone?

No. Penal Code 1111 provides that a conviction cannot be had on the testimony of an accomplice unless it is corroborated by other evidence that tends to connect the defendant with the commission of the offense. The corroboration need not be strong, but it must be independent of the accomplice's account and must point to the defendant, not merely show that the crime occurred. Juries are instructed to view accomplice testimony with caution, and the rule is one of the main defenses in cases built on a cooperating co-defendant.

Related reading from our attorneys

• Aiding and abetting under Penal Code 31
• Accessory after the fact under Penal Code 32
• Criminal conspiracy: the agreement to commit a crime

Charged for what someone else did? Knowledge and timing decide the case

The Bulldog Law's criminal defense attorneys defend aiding and abetting, conspiracy, and accessory charges across California, including Penal Code 1172.6 resentencing petitions for clients convicted of murder as accomplices under the old rules. Call (888) 928-1609 or reach us online.