Updated September 2026 | The Bulldog Law | California Criminal Defense
Aiding and abetting means knowingly helping another person commit a crime, with the intent that the crime succeed. California does not treat it as a lesser offense. Under Penal Code 31, everyone concerned in the commission of a crime, whether they directly commit it or aid and abet it, is a principal, and a principal is charged with, convicted of, and sentenced for the crime itself. The getaway driver is guilty of the robbery; the lookout is guilty of the burglary. The prosecution has to prove three things: the aider knew the perpetrator's unlawful purpose, intended to help or encourage it, and actually did something, by act or by words, that aided it. Being present is not enough. Knowing about it is not enough. And since 2019, aiding a lesser crime no longer makes a person guilty of a murder someone else committed.
The Bulldog Law's attorneys defend more aiding and abetting cases than clients realize, because the charge rarely appears by name. It appears as a robbery count against the person who was in the car, an assault count against the friend who was standing nearby, a burglary count against the girlfriend who drove. The question in every one of those cases is the same: what did this person know, what did they intend, and what did they actually do. What follows is how California answers it, the doctrine that changed in 2019, and the defenses that separate the participant from the bystander. If you've been charged for something someone else did, call (888) 928-1609 or message our team.
Penal Code 31: there are no minor players
Penal Code 31 says that all persons concerned in the commission of a crime, whether it be felony or misdemeanor, and whether they directly commit the act constituting the offense, or aid and abet in its commission, or, not being present, have advised and encouraged its commission, are principals in any crime so committed. The consequence is total: California abolished the old distinctions between principals in the first and second degree and accessories before the fact, and folded everyone who helped before or during the crime into one category, punished identically to the person who pulled the trigger, took the money, or threw the punch.
So there is no aiding and abetting sentence. A person who aided a robbery is sentenced for robbery, two, three, or five years for second degree, three, four, or six for first, with the same enhancements the perpetrator faces. What a judge can do is consider the aider's lesser role as mitigation, and our attorneys spend a great deal of sentencing effort on exactly that distinction. What the statute will not do is convert the charge into something smaller by itself.
The three elements, and the one that matters
California's jury instruction, CALCRIM 401, requires the prosecution to prove that the perpetrator committed the crime, that the defendant knew the perpetrator intended to commit it, that before or during its commission the defendant intended to aid and abet it, and that the defendant's words or conduct did in fact aid and abet it. Knowledge, intent, and an act. The California Supreme Court settled in People v. Beeman in 1984 that the intent element is real: the aider must share the perpetrator's purpose or intend to facilitate it, not merely know it exists.
Intent is where these cases are won. Knowledge is often provable: the defendant was there, the plan was discussed in front of them, the texts exist. The act is often trivial: driving, waiting, opening a door. What the prosecution frequently cannot prove is that the defendant meant to help the crime happen rather than, say, meant to get a ride home, or froze, or went along without understanding what was planned. Juries take that element seriously when it is argued seriously.
What is not aiding and abetting
Presence at the scene. Knowledge that a crime is occurring. Failure to prevent it, unless the person had a legal duty to act. Association with the perpetrator. Being in the car without knowing the plan. Helping after the fact, which is a different crime discussed below. Prosecutors charge on presence and association constantly, particularly in group settings, and the weakness of those cases shows up as soon as the defense asks what, exactly, the defendant did.
Words alone can be enough
The statute reaches those who, not being present, advised and encouraged the crime. A person who tells a friend where the victim will be, or urges them to go through with it, or promises to handle the aftermath, can be a principal without leaving the house. Text messages have made this theory far more common than it used to be, and the same messages that prove knowledge are read by prosecutors as proof of encouragement. Our attorneys read them differently, and the context, the whole thread, the tone, what was said in reply, is usually the defense.
Aiding and abetting versus accessory versus conspiracy
Three doctrines get confused, and the differences are large.
An aider and abettor helps before or during the crime and is guilty of that crime. An accessory after the fact, under Penal Code 32, helps afterward: harbors, conceals, or aids a person they know committed a felony, with intent to help them escape arrest, trial, or punishment. Hiding the perpetrator, destroying evidence, lying to police about where they are. It is a separate wobbler carrying up to three years, and it is not the underlying crime; our attorneys cover it on our accessory after the fact page. The line is time: the driver who brought the robber to the bank is a principal in the robbery; the friend who let him sleep in the garage that night is an accessory.
Conspiracy, under Penal Code 182, is an agreement between two or more people to commit a crime plus an overt act toward it, and it is complete before any crime occurs. A conspirator can be guilty of conspiracy even if the target crime never happens, and guilty of the target crime and of conspiracy if it does. Aiding and abetting requires no agreement, just knowing help. The two overlap constantly, and a prosecutor who cannot prove an agreement will fall back on aiding and abetting, or the reverse.
The natural and probable consequences doctrine, and what SB 1437 did to it
For most of California's history, an aider and abettor was liable not only for the crime they intended to help but for any other crime that was a natural and probable consequence of it. A person who helped with an assault could be convicted of murder if the victim died, even though they never intended a killing and may not have known the perpetrator was armed. That doctrine sent thousands of people to prison for life on murder convictions built on a lesser intent.
Senate Bill 1437, effective in 2019, abolished natural and probable consequences liability for murder. To be convicted of murder now, an aider and abettor must have personally acted with malice, intended to kill, or, in a felony murder case, been a major participant who acted with reckless indifference to human life. Senate Bill 775 extended the change to attempted murder and voluntary manslaughter in 2022. The same bills created Penal Code 1172.6, which lets people convicted under the old theory petition to have the murder conviction vacated and be resentenced on whatever they actually did. Our page on SB 1437 and Penal Code 1172.6 resentencing explains the petition, and our attorneys have filed them for clients who were teenagers when a friend's fight turned into a homicide.
The doctrine still exists for non-homicide crimes. A person who aids an assault can still be convicted of a robbery that was a natural and probable consequence of it, and prosecutors use the theory in gang cases, group attacks, and burglaries that escalate. The test is whether a reasonable person in the aider's position would have known the other crime was likely, judged objectively, and it remains one of the most litigated questions in California criminal law. In murder cases, though, the question is now what the aider themselves intended, which is the question it should have been all along.
Defenses
No knowledge. The person who drove without knowing what the passenger planned, or who was invited along under a false description of the outing, lacked the knowledge element. This is common and credible, and it turns on what was said beforehand.
No intent to aid. The person knew but didn't share the purpose or intend to facilitate it: a bystander who stayed out of fear, a passenger who didn't want to be there, a friend who said something in a group chat without meaning to encourage anyone. Beeman makes this a real defense, not a technicality.
No act. Nothing the defendant did or said actually aided the crime. Presence, silence, and association are not acts.
Withdrawal. A person who initially intended to help can escape liability by withdrawing before the crime: they must notify the other participants that they are no longer part of it and do everything reasonably within their power to prevent the crime. Leaving quietly is not withdrawal; calling the police, or telling the others clearly and trying to stop it, can be.
Duress, mistaken identity, and the perpetrator's acquittal. An aider forced to participate under an immediate threat of death or great bodily injury has a defense. Identity is contested in group cases where witnesses saw a crowd. And while an aider can be convicted even if the perpetrator is never caught, the prosecution still has to prove that the underlying crime was actually committed by someone.
The interview. Aiding and abetting cases are built from statements: the defendant's own account of where they were and what they knew, given to a detective who framed the conversation as a chance to explain that they were only the driver. Only the driver is a confession under Penal Code 31. The right to remain silent exists for this, and so does the right not to be pressured into testifying against a co-defendant without counsel.
Sentencing and consequences
Because an aider is sentenced under the underlying statute, everything about that statute applies: strikes, enhancements, custody credit limits, registration where the crime requires it. What the aider's role changes is the argument. Rule of Court 4.423 lists a passive or minor role as a mitigating factor, and our attorneys present it with evidence: who planned, who profited, who was armed, who was 17 and in the back seat. That argument decides whether counts run concurrently or consecutively, whether the low term applies, and in wobbler cases whether the conviction is a felony at all. For non-citizens, the aider faces the immigration consequences of the crime itself, since federal law treats an aiding and abetting conviction as a conviction for the offense. And for minors, who make up a large share of aiders in group crimes, the juvenile system applies its own rules.
Frequently asked questions
What does aiding and abetting mean?
Helping someone commit a crime while knowing what they intend and meaning to help them do it. In California, an aider and abettor is a principal under Penal Code 31, which means the law treats them as if they committed the crime themselves. The getaway driver is guilty of the robbery. The person who held the door is guilty of the burglary. The friend who texted where the victim would be is guilty of the assault.
What is the sentence for aiding and abetting in California?
The same as for the crime itself. There is no separate aiding and abetting offense with its own penalty; Penal Code 31 makes the aider a principal, so a person who aided a robbery is sentenced under the robbery statute, two to nine years, and can face the same enhancements. Judges can and do treat the aider's lesser role as a mitigating factor at sentencing, but the maximum is the perpetrator's maximum.
Is being present at a crime aiding and abetting?
No. Presence at the scene, knowledge that a crime is happening, and even failing to stop it are not enough. The prosecution must prove you knew the perpetrator's purpose, intended to help, and actually did something, by act or by words, that aided or encouraged. Someone who stood there and watched, or who was in the car without knowing what was planned, is not an aider and abettor, although prosecutors often charge them as one and let the jury sort it out.
What is the difference between aiding and abetting and being an accessory?
Timing. An aider and abettor helps before or during the crime and is punished as a principal for that crime. An accessory after the fact, under Penal Code 32, helps afterward, by hiding the person, destroying evidence, or lying to police, knowing they committed a felony, and is punished for a separate, lesser wobbler carrying up to three years. The person who drove the robber to the bank is an aider; the person who let him hide in their garage that night is an accessory.
Can I be charged with murder for aiding a different crime?
Much less often than before 2019. Under the old natural and probable consequences doctrine, a person who aided an assault could be convicted of murder if a death was a foreseeable result. Senate Bill 1437 abolished that theory for murder, and Senate Bill 775 extended the change to attempted murder and manslaughter. Now an aider can be convicted of murder only if they themselves acted with intent to kill or were a major participant acting with reckless indifference to life. People convicted under the old rule can petition for resentencing under Penal Code 1172.6.
Related reading from our attorneys
- Accessory after the fact under Penal Code 32
- SB 1437 and Penal Code 1172.6 resentencing
- Murder prosecutions under Penal Code 187
Charged for something someone else did? The question is what you knew
The Bulldog Law's defense attorneys handle aiding and abetting, conspiracy, and accessory cases across California, from group assaults to homicides, and we file Penal Code 1172.6 petitions for clients convicted under the old natural and probable consequences rule. Visit our criminal defense page, call (888) 928-1609, or reach us online.