You’re staring at an MBE question where Dan hands Steve a crowbar and says “break the window while I keep watch,” and now you’re trying to figure out whether Dan is guilty of burglary even though he never touched the building. Welcome to accomplice liability on the MBE — one of the most tested doctrines in Criminal Law, and one that trips up even strong students because it layers intent requirements on top of each other.

Here’s what you need to know to spot accomplice liability issues and apply the rules correctly under time pressure.

What Is Accomplice Liability?

Accomplice liability makes a defendant criminally responsible for someone else’s crime if the defendant intentionally aided, encouraged, or facilitated its commission. The accomplice doesn’t have to commit the actus reus of the underlying offense. They can be convicted of the same crime as the principal — the person who actually committed it — based on their assistance.

The MBE tests this constantly because it requires you to analyze two levels of intent simultaneously: intent to help and intent that the underlying crime be committed.

The traditional labels you’ll see are principal (the person who commits the crime with their own hands) and accomplice (the person who aids, abets, encourages, or assists). At common law, there were finer distinctions — principals in the first degree, principals in the second degree, accessories before the fact — but modern law and the MBE collapse these into a simpler framework. An accomplice is liable for the substantive offense itself.

The Two-Part Test for Accomplice Liability

To hold someone liable as an accomplice, the prosecution must prove two elements:

1. The defendant aided, encouraged, or assisted the principal in committing the crime. This is the actus reus of accomplice liability. It can include physical help (providing tools, weapons, transportation), encouragement (urging the principal on), or even just serving as a lookout. Mere presence at the scene is not enough unless the defendant has a legal duty to intervene or their presence encourages the crime.

2. The defendant had the intent to assist the principal AND the intent that the principal commit the underlying offense. This is where students get tangled. Accomplice liability is a specific intent crime even when the underlying offense is a general intent crime. You must intend to help, and you must intend that the crime actually happen.

Let’s break down what this means in practice.

The Intent Requirement: Why It’s Trickier Than You Think

The intent element has two components, and both must be present.

Intent to assist: The defendant must purposefully provide aid. Accidental assistance doesn’t count. If you unknowingly sell someone a gun they later use in a robbery, you’re not an accomplice because you lacked intent to help with the crime.

Intent that the crime be committed: This is the part that catches people. The accomplice must want or have the purpose that the underlying crime occur. Knowledge that a crime will occur is generally not sufficient by itself — the accomplice must share the principal’s criminal objective.

Example: You sell a customer rope, and you know he’s planning to use it to tie up a victim during a kidnapping. Are you an accomplice to kidnapping? Under the majority rule, probably not, unless you sold the rope for the purpose of facilitating the kidnapping. Mere knowledge isn’t enough for accomplice liability. You’d need to have the intent that the kidnapping succeed.

This rule has a major exception: if the crime requires only recklessness or negligence (like involuntary manslaughter), the accomplice can be liable if they intentionally aid conduct they know creates the risk, even without specific intent for the result. But for specific intent crimes, the accomplice must share that specific intent.

Accomplice Liability for Specific Intent vs. General Intent Crimes

Here’s a distinction that shows up constantly on the MBE: when the underlying crime is a specific intent crime, the accomplice must have that same specific intent.

Take burglary (the breaking and entering of the dwelling house of another at nighttime with the intent to commit a felony therein). If Dan helps Steve break into a house, Dan is only liable for burglary if Dan intended that Steve commit a felony inside. If Dan thought Steve was just going to retrieve his own property, Dan lacks the specific intent for burglary even though he helped with the breaking and entering.

For general intent crimes like battery (the unlawful application of force to the person of another), the accomplice must intend to aid the act that constitutes the crime and intend that the act occur, but doesn’t need to intend the specific harmful result if the principal didn’t either.

The MBE loves to test this by giving you a fact pattern where the accomplice aids the principal but misunderstands the principal’s ultimate goal. Always ask: did the accomplice have the mental state required for the underlying offense?

Mere Presence vs. Active Encouragement

You’re at a bar. Your friend suddenly punches someone. Are you an accomplice to battery just because you were standing there?

No. Mere presence at the scene of a crime is not enough for accomplice liability, even if you secretly approve of what’s happening. There must be some affirmative act of assistance or encouragement.

However, presence can be enough if:

The MBE will test whether the defendant crossed the line from passive observer to active participant. Look for facts showing the defendant did something — even something small like nodding approval, providing information, or positioning themselves to help.

Accomplice Liability and the Natural and Probable Consequences Doctrine

Under the traditional natural and probable consequences doctrine, an accomplice can be liable not only for the crime they intended to aid, but also for any other crimes committed by the principal that were a natural and probable consequence of the original crime.

Example: You agree to help your friend commit a robbery by driving the getaway car. During the robbery, your friend unexpectedly shoots the store clerk. Are you liable for murder?

Under the natural and probable consequences doctrine, yes — if the shooting was a reasonably foreseeable result of the armed robbery. You intended to aid the robbery, and the murder was a natural and probable consequence of that felony.

This doctrine has been criticized and abolished in some jurisdictions (notably California), but it remains the majority rule and is still tested on the MBE. The key is foreseeability: the additional crime must be within the scope of the criminal enterprise the accomplice agreed to assist.

Note the parallel here with the Pinkerton rule for conspiracy: each conspirator is liable for all foreseeable crimes committed by co-conspirators in furtherance of the conspiracy. Accomplice liability operates similarly, though the doctrines are technically distinct.

Withdrawal: Can You Stop Being an Accomplice?

What if you change your mind after agreeing to help but before the crime is completed? Can you withdraw from accomplice liability?

Yes, but it’s difficult. To effectively withdraw, the accomplice must:

Mere change of heart is not enough. The accomplice must take steps that deprive their prior aid of effectiveness. If you provided the principal with a gun and then just walk away, you haven’t withdrawn — you need to get the gun back or warn the victim.

Withdrawal is an affirmative defense, meaning the defendant bears the burden of proving it. The MBE tests this by giving you a fact pattern where someone tries to back out but doesn’t go far enough to meet the legal standard.

Accessory After the Fact: A Different Animal

Don’t confuse accomplice liability with being an accessory after the fact. An accessory after the fact is someone who, knowing a felony has been committed, assists the felon in avoiding arrest or prosecution (like hiding them, destroying evidence, or providing a false alibi).

This is a separate, lesser offense — not accomplice liability to the underlying crime. The accessory after the fact is not guilty of the felony itself, only of the crime of obstructing justice.

The MBE occasionally includes this as a wrong answer choice. If someone helps after the crime is complete, they’re an accessory after the fact, not an accomplice.

How the MBE Tests Accomplice Liability

The bar examiners love accomplice liability because it tests your ability to layer mental states and apply them to nuanced facts. Here are the patterns you’ll see:

Scenario 1: The defendant provides assistance but lacks intent for the crime. The defendant sells materials or provides help without knowing they’ll be used for criminal purposes, or knows but doesn’t share the criminal objective. Correct answer: not liable as an accomplice.

Scenario 2: The defendant intends to help with Crime A, but the principal commits Crime B. Was Crime B a natural and probable consequence of Crime A? If yes, accomplice liability attaches. If no, the defendant is only liable for Crime A.

Scenario 3: The defendant is present and does nothing. Was there a legal duty to act? Did the presence provide encouragement? If neither, no accomplice liability.

Scenario 4: The defendant tries to withdraw. Did they communicate withdrawal or neutralize their aid in time? If not, they remain liable.

The key to these questions is methodically working through the two-part test: aid + intent. Don’t skip the intent analysis just because the defendant obviously helped.

What to Memorize for Test Day

When you see an accomplice liability issue on the MBE, run this checklist:

  1. Did the defendant aid, encourage, or assist? Look for affirmative acts, not just presence.

  2. Did the defendant intend to assist? Was the help purposeful or accidental?

  3. Did the defendant intend that the principal commit the underlying crime? Knowledge alone usually isn’t enough — look for shared purpose.

  4. If the principal committed additional crimes, were they natural and probable consequences of the crime the accomplice intended to aid?

  5. Did the defendant effectively withdraw before the crime was completed?

If you can answer those five questions, you can handle any accomplice liability question the MBE throws at you.

Accomplice liability is one of those doctrines where the rules are straightforward but the application requires careful attention to facts. The MBE will bury the key detail — whether the defendant actually intended the crime or just knew about it — in the middle of a dense fact pattern. Train yourself to spot the intent language.

If you’re looking for all the accomplice liability rules (plus conspiracy, attempt, and the Pinkerton rule) organized in one place for active recall, FlashTables Criminal Law & Procedure breaks down every element you need to memorize in a two-column format designed specifically for MBE prep. The structured layout helps you see how accomplice liability connects to other inchoate crimes and parties doctrines, so you’re not memorizing rules in isolation. You can check it out at getflashtables.com.

Now go practice spotting when someone crosses the line from bystander to accomplice. That’s the skill that earns points on test day.