Civil conspiracy in Massachusetts — two forms, and the rare one is nearly unusable

Massachusetts has two civil conspiracy doctrines, and they are not variations on a theme. One is a freestanding tort that almost nothing satisfies. The other is a way of spreading liability for someone else's tort.

Pleading the wrong one is the most common error in this area, and it is usually fatal, because the rare form is dismissed on the pleadings and the useful form is not a "conspiracy" claim at all.

The two forms

True conspiracy — the coercive form. A narrow cause of action requiring that the defendants, by acting in unison, had some peculiar power of coercion over the plaintiff that they would not have had acting independently.

This is the older doctrine, and it comes from cases about combinations that could destroy a business through concerted refusal to deal. Massachusetts courts describe it as "very limited," and it fails whenever any individual defendant could have inflicted the same harm alone.

Concerted action — the useful form. Liability for substantially assisting or encouraging another's tortious conduct, or for acting in pursuance of a common design. This is a theory of joint liability, not an independent wrong: there must be an underlying tort, and the conspiracy count attaches liability for it to people who did not personally commit it.

What a plaintiff has to prove

Coercive conspiracy:

1. A combination of two or more persons;
2. Acting in unison, giving them a peculiar power of coercion over the plaintiff;
3. That no defendant would have possessed acting alone; and
4. Damage.

Concerted action:

1. A common design or agreement, express or tacit, to commit a tortious act;
2. The defendant's substantial assistance or encouragement of the conduct, or performance of part of it;
3. Knowledge that the conduct constituted a breach of duty; and
4. An underlying tort committed in fact, causing damage.

The fourth element of the second form is the one that decides most cases. Kill the underlying tort and the conspiracy claim dies with it.

Why the coercive form fails

The peculiar-power requirement is doing deliberate work. If two competitors defraud a customer, each of them could have defrauded the customer alone — so the combination added nothing coercive, and the claim is one of ordinary fraud with two defendants.

What the doctrine was built for is the case where the combination itself is the instrument: a group of suppliers who together control the only source, a set of lenders who together control the credit a business needs. Take one away and the pressure disappears.

That fact pattern is rare, and courts say so. A complaint that pleads "conspiracy" without alleging that the defendants' union created a coercive power none of them held individually is pleading the wrong tort.

Aiding and abetting

Massachusetts also recognises aiding and abetting liability for a tort, and it is closely related to concerted action:

1. The primary actor committed a tort;
2. The defendant knew of the breach of duty; and
3. The defendant actively participated in or substantially assisted it.

This is the theory that reaches the professional adviser — the lawyer, accountant or bank that helped a fiduciary breach a duty or a debtor hide assets. Knowledge is the fought element, and constructive knowledge is generally not enough; what is required is actual knowledge of the underlying wrong.

See breach of fiduciary duty, where this theory does most of its work.

How long you have to file

The underlying tort's period. Conspiracy carries no limitations period of its own, because outside the rare coercive form it is not an independent wrong.

Three years under G.L. c. 260, § 2A for most torts. Four years where the underlying claim is a 93A claim under c. 260 § 5A. Six years where the underlying wrong is a breach of contract — though a conspiracy to breach a contract is generally not actionable at all, since breach of contract is not a tort.

What has to happen before you file

Nothing. But plead the facts of the agreement, not the conclusion. A complaint alleging that defendants "conspired and agreed" without saying what was agreed, when, or how the defendant assisted will be dismissed.

What the claim pays

The damages caused by the underlying tort, recoverable from every participant jointly and severally. That is the entire value of the theory: a defendant with assets can be made to pay a judgment earned against one without.

Whatever the underlying tort provides — exemplary damages if it carries them, fees if it carries them. Conspiracy adds no remedy of its own.

Twelve percent interest.

Who can be sued

Each participant in the common design, including those who did no part of the act themselves.

A professional adviser, on the aiding and abetting theory, where they knew of the breach and substantially assisted it.

Not a corporation and its own agents, generally. The intracorporate conspiracy doctrine treats a company and its employees acting within the scope of employment as a single actor — there is no combination of two or more persons.

Common defenses

• No underlying tort, which is fatal to the concerted-action form.
• No peculiar power of coercion, which is fatal to the true conspiracy form.
• No agreement — parallel conduct, a shared interest, or a business relationship is not a common design.
• No knowledge of the underlying breach, which defeats aiding and abetting.
• The intracorporate conspiracy doctrine.
• Limitations, on the underlying tort's period.
• Conclusory pleading, dismissed under Rule 12.

What people get wrong

There are two doctrines, and they are different. The coercive form is a tort; the concerted-action form is a liability theory.

The coercive form almost never applies. If any defendant could have caused the harm alone, it fails.

Conspiracy adds defendants, not damages. It does not increase the recovery; it increases who can be made to pay it.

There must be an underlying tort. A conspiracy to do something lawful, or to breach a contract, is not actionable.

A company cannot conspire with its own employees acting in the scope of employment.

"Defendants conspired" is not a pleading. Say what was agreed, and what each defendant did.

Where it came from

Civil conspiracy grew out of the criminal doctrine, where the agreement itself is the offence because a group planning a crime is more dangerous than a person planning one. That reasoning does not transfer cleanly to tort, where the plaintiff has been injured by conduct rather than by an agreement, and courts spent a long time working out what an agreement adds.

Massachusetts answered the question narrowly, and gave its reason. Where the combination itself is what produces the harm — where a group can coerce because it acts as one — the agreement is the wrong, and the tort exists. Where the combination merely means several people committed a tort together, the agreement adds nothing to the plaintiff's injury and the appropriate doctrine is joint liability for the tort, not a separate claim.

That is why the coercive form is described as narrow and the concerted-action form is described as a theory. The distinction is not a technicality; it reflects a decision about what a conspiracy allegation is for.

The practical consequence for a plaintiff is that the conspiracy count is worth pleading for reach rather than for value. It brings in the people who financed, assisted or directed the wrong, and makes each of them answerable for the whole judgment — which is often the difference between a claim worth bringing and one that is not.

Common questions

Is civil conspiracy a claim in Massachusetts?

Two things go by that name. A narrow true conspiracy tort requiring coercive power the defendants had only by acting together, and a concerted-action theory of joint liability that requires an underlying tort.

How long do I have to sue?

Whatever period applies to the underlying tort — three years for most, four for a 93A claim.

Does conspiracy increase my damages?

No. It increases who can be made to pay them, jointly and severally.

Can I sue a company and its own employees as conspirators?

Generally no. The intracorporate conspiracy doctrine treats them as one actor.

Can I sue the accountant or lawyer who helped?

On an aiding and abetting theory, yes — if they knew of the underlying breach of duty and substantially assisted it. Actual knowledge is required.

What has to be in the complaint?

The facts of the agreement and each defendant's role. A conclusory allegation that the defendants conspired will be dismissed.

Where these rules live

• Mass. R. Civ. P. 8 — General rules of pleading
• Mass. R. Civ. P. 9 — Pleading special matters
• Mass. R. Civ. P. 12 — Defenses and objections
• Mass. R. Civ. P. 20 — Permissive joinder of parties
• Mass. R. Civ. P. 56 — Summary judgment
• Motion to dismiss in Massachusetts