19.4 Parties to Crime: Principals, Accomplices & Accessories After the Fact
Key Takeaways
- At common law, parties were principals in the first degree (who commit the crime), principals in the second degree (who aid at the scene), accessories before the fact (who aid beforehand but are absent), and accessories after the fact; modern law treats all but accessories after the fact as accomplices liable for the crime itself.
- Accomplice liability requires conduct that aids, abets, encourages, or procures the crime and intent both to assist and that the crime be committed; mere presence or knowledge is not enough, though a supplier's stake in the venture may show intent.
- Many jurisdictions hold an accomplice liable for other crimes that are natural and probable consequences of the intended crime, but the MPC limits liability to crimes the accomplice intended to promote or facilitate; for crimes defined by recklessness or negligence, the accomplice needs that culpability as to the result.
- An accomplice may withdraw before the crime by repudiating encouragement or neutralizing assistance—for example, retrieving supplied tools or timely warning the police—and the principal's acquittal does not bar the accomplice's conviction in modern law (Standefer v. United States).
- A person whom a statute is designed to protect, such as a minor in a statutory rape case, is not an accomplice, and an accessory after the fact who knowingly helps a felon avoid arrest commits a separate, lesser offense rather than the felony itself.
19.4 Parties to Crime: Principals, Accomplices & Accessories After the Fact
Accomplice liability is not a separate crime; it is a way of holding a person responsible for a crime someone else physically commits. Accessories after the fact are treated differently, because they help only after the crime is over. NCBE's outline lists parties to crime alongside the inchoate offenses.
Accomplice Liability
Accomplice liability is not an independent crime; it is a mechanism by which a secondary party is held derivatively liable for the substantive offenses committed by the principal.
1. Elements of Accomplice Liability
To be convicted as an accomplice, the prosecution must prove two distinct elements:
- Actus Reus: The defendant aids, abets, counsels, encourages, commands, or facilitates the principal's commission of the crime, or provides physical assistance (e.g., procuring getaway car, acting as lookout).
- Mens Rea (Dual Intent): The accomplice must act with: (a) the intent to assist the principal; and (b) the intent that the principal commit the target offense.
MBE Red Herring — Mere Presence & Mere Knowledge: Mere presence at the crime scene, even with knowledge that a crime is being committed, does not make one an accomplice. Similarly, mere knowledge that a customer will use a purchased product for a criminal act (e.g., selling ordinary gasoline to an arsonist) is generally insufficient for accomplice liability unless the supplier has a stake in the venture or charges an exorbitant price.
2. Scope of Accomplice Liability
Under the natural and probable consequences doctrine, an accomplice is guilty of:
- The target offense aided and abetted; and
- Any other crimes committed by the principal that were natural, foreseeable consequences of the intended crime.
3. Accessory After the Fact
An accessory after the fact is one who receives, comforts, relieves, or assists a felon, knowing that the person has committed a completed felony, for the purpose of hindering the felon's apprehension, arrest, trial, or punishment. Unlike common law accomplices, an accessory after the fact is not liable for the underlying felony itself, but is guilty of a separate, distinct obstruction-of-justice offense carrying a lesser penalty.
4. Withdrawal / Abandonment from Accomplice Liability
To effectively withdraw and escape criminal liability for subsequent offenses, the accomplice must neutralize their prior assistance before the crime is committed:
- Repudiation: If the accomplice provided encouragement, they must repudiate that encouragement to the principal before the crime occurs.
- Neutralization: If the accomplice provided physical materials (such as a weapon or keys), they must render the assistance ineffective (e.g., taking back the weapon or calling the police to thwart the crime).
- Timing: Withdrawal must occur before the chain of events becomes unstoppable.
Applying Accomplice Liability Rules
Common-Law Categories
| Category | Role | Modern Treatment |
|---|---|---|
| Principal in the first degree | Commits the act constituting the crime, personally or through an innocent agent | Principal |
| Principal in the second degree | Present at the scene and aids or encourages (including a lookout or getaway driver nearby) | Accomplice, liable for the crime |
| Accessory before the fact | Aids, counsels, or encourages before the crime but is not present | Accomplice, liable for the crime |
| Accessory after the fact | Knowingly helps a felon avoid arrest, trial, or punishment after the felony | Separate, lesser offense (often called hindering prosecution) |
At common law, an accessory could not be convicted unless the principal was convicted first. Modern law abolishes that rule: an accomplice may be convicted even if the principal is acquitted, never prosecuted, or immune (Standefer v. United States, 1980).
Mental State Issues
- Advance knowledge: A person charged with aiding and abetting the use of a firearm during a drug crime must have known in advance that a confederate would carry a gun, while there was still a realistic opportunity to withdraw (Rosemond v. United States, 2014).
- Crimes of recklessness or negligence: An accomplice who encourages reckless conduct may be liable for a resulting death if the accomplice shares the required recklessness—for example, handing car keys to an obviously drunk friend and urging him to drive fast.
- Innocent agents: A person who uses an innocent or irresponsible agent—a young child, a person who is insane, or someone deceived about the facts—to commit a crime is the principal.
- Different degrees of guilt: Each participant's guilt depends on that participant's own mental state. A principal who kills in a sudden heat of passion may be guilty of voluntary manslaughter while an accomplice who calmly encouraged the killing is guilty of murder.
Exemptions and Defenses
- Protected persons: A person whom the statute is designed to protect cannot be convicted as an accomplice to that crime, such as a minor who willingly participates in statutory rape (MPC § 2.06(6)(a); see Gebardi v. United States).
- Conduct inevitably incident to the crime: A person whose conduct is inevitably incident to the offense is not an accomplice unless the statute provides otherwise (MPC § 2.06(6)(b)).
- Principal's defenses: An excuse personal to the principal, such as insanity or duress, does not protect an accomplice. A justification, such as self-defense, means no crime occurred, so no one is liable as an accomplice.
- Feigned principal: If the "principal" is an undercover officer who never intends to commit the crime, there is no completed crime to which the helper can be an accomplice, but the MPC treats the helper's conduct as an attempt (§ 5.01(3)).
Accessory After the Fact and Related Crimes
- Elements: A completed felony; knowledge that the felony was committed; and personal assistance to the felon with intent to help the felon avoid arrest, trial, conviction, or punishment.
- No general duty to report: Simply failing to report a crime is not a crime. Federal misprision of felony requires an affirmative act of concealment, such as lying to investigators or hiding evidence, in addition to knowledge and failure to report (18 U.S.C. § 4).
- Relatives: Some states exempt close relatives from liability as accessories after the fact.
| Method of Withdrawal | Encouragement Only | Material Assistance Provided |
|---|---|---|
| Effective if made before the crime becomes unstoppable | Repudiate the encouragement to the principal | Neutralize the aid (retrieve the tool or key) or give timely warning to police |
| Ineffective | Silently leaving the scene | Merely telling the principal "don't do it" while the aid remains usable |
A tenant agreed to help a friend burglarize an electronics warehouse. The tenant provided the friend with a duplicate master key to the warehouse service door, intending that the friend enter and steal high-end laptops. Two hours before the planned burglary, the tenant had a change of heart, texted the friend stating 'I cannot be involved in this, do not do it,' and turned their phone off. The friend used the duplicate key anyway, broke in, and stole fifty laptops. Is the tenant liable as an accomplice for the burglary?
A 15-year-old girl persuaded her 20-year-old boyfriend to have sexual intercourse with her, and they did so. A state statute makes it a felony for any person to have sexual intercourse with a person under 16 years of age. The prosecutor charged the boyfriend with statutory rape and charged the girl as an accomplice to statutory rape, arguing that she solicited and encouraged the act. Can the girl be convicted as an accomplice?
A man robbed a convenience store at gunpoint. That night, he went to a friend's apartment, told her what he had done, and asked to hide there. She let him stay for two days, falsely told police officers who came looking for him that she had not seen him, and gave him money for a bus ticket out of state. She had no advance knowledge of the robbery and had never discussed it with him before it happened. Of which crime is the friend most likely guilty?