Also known as: act in concert · acted in concert · acts in concert · acting in concert with · concerted action
Written by attorneys · grounded in primary & secondary sources — see below
Coordinated action by two or more persons pursuant to a common plan or design that makes each participant responsible for the conduct of the others. The coordination supplies the basis for extending liability or binding effect beyond the direct actor to those who assisted or encouraged the conduct.
An employer entrusted its bookkeeper with authority to process incoming checks. The bookkeeper recruited a friend to forge the employer's indorsement on a check made payable to the employer and deposit the proceeds into a joint account. Because the friend acted in concert with the bookkeeper, the forged indorsement is treated as effective against a bank that paid the instrument in good faith.
Several local merchants sued organizers and participants in a consumer boycott for damages caused by lost sales. The organizers had planned the boycott and encouraged others to withhold patronage. Because the participants acted in concert with the organizers under a common design, each could be held jointly liable for the resulting harm even if some individuals committed no independent tortious act.
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Two motorcyclists raced each other on a public highway at high speed. One lost control and struck a pedestrian. Because the racers were acting in concert by engaging in the illegal competition, each is liable for the full extent of the pedestrian's injuries regardless of which motorcycle made contact.
Two hunters fired negligently in the same direction toward a shared target area. One pellet struck the plaintiff. Because the hunters were acting in concert by hunting together without taking precautions, both are jointly and severally liable for the plaintiff's injuries even though only one pellet caused the harm.
Several pharmaceutical companies produced and marketed the same drug using an identical formula without coordinating testing or warnings. Because the companies acted in concert by relying on each other's safety data and marketing practices, each could be held liable for a plaintiff's injury even without proof that any particular defendant's product caused the harm.
A dominant aluminum producer entered agreements with competitors to allocate production quotas and geographic markets. Because the producer and its rivals acted in concert to restrict output and fix prices, the coordinated conduct violated antitrust prohibitions and exposed each participant to liability for the resulting market harm.
No. Courts infer concerted action from coordinated conduct, shared plans, or mutual encouragement even without a formal contract. The Restatement focuses on whether the parties planned, assisted, or encouraged the tortious act under a common design.
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A nonparty who receives actual notice of an injunction and acts in active concert with an enjoined party to violate its terms may be held in contempt. This prevents an enjoined defendant from evading the order by directing third parties to carry out the prohibited conduct.
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When multiple tortfeasors act pursuant to a common plan or design, each is liable for the entire harm caused by any participant's tortious conduct. This rule survives in many jurisdictions even after reforms limiting joint liability for independent tortfeasors.
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Yes. Under UCC § 3-405(b), if an employee entrusted with responsibility for instruments acts with another person to make a fraudulent indorsement, the indorsement binds the employer as if made by the employer itself when the instrument reaches a good-faith taker.
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…stand. It is argued by defendants that they are not joint tort feasors, and thus jointly and severally liable, as they were not acting in concert, and that there is not sufficient evidence to show which defendant was guilty of the negligence which caused the injuries—the shooting by Tice or that by Simonson. Tice argues that there is…