We saw in the chapters on causation that a plaintiff will frequently have claims against more than one tortfeasor, where several have contributed to causing her injury. This chapter, and the next, address the manner in which tort law distributes the damages in such cases. This chapter deals with the traditional common law rules governing the liability of “joint tortfeasors.” The next analyzes principles of contribution, the right of a tortfeasor who has paid the plaintiff’s claim to seek partial reimbursement from other defendants liable for the same injury.
First, let’s distinguish the case of “true” joint tortfeasors from the much more common type of joint and several liability discussed in this chapter. True joint tortfeasors are parties who agree to engage in a course of tortious conduct. Suppose that Kelvin and Curie go looking for Marconi, planning to beat him up. They find him, and Curie breaks his jaw. Because Kelvin and Curie acted in concert to injure Marconi, both are liable to him, even though it was Curie who administered the blow. Although Kelvin didn’t hit Marconi, he encouraged and participated in the common scheme to injure Marconi. Tort law traditionally held-and still holds-actors involved in such joint conduct liable for the acts of either, in much the same way that conspirators are criminally responsible for the acts of other conspirators. See Restatement (Third) of Torts: Apportionment of Liability §15. Similarly, if Ford and Hudson decide to race their cars on the highway, they are both liable if one of their cars hits Lenoir, since they jointly engaged in the negligent conduct that led to Lenoir’s injury.
Such “true” joint tortfeasor cases, in which parties agree to engage in tortious conduct, are relatively rare. It is much more common for the independent conduct of two actors to combine to injure the plaintiff. Suppose, for example, that Fermi was a passenger in Joule’s car, which collided with a truck driven by Edison due to negligence by both drivers, and that Fermi suffered a broken collar bone. Here, Edison and Joule did not act together, probably did not know each other, may not even have known of the other’s presence. However, their independent acts have contributed to cause a single injury. As we saw in the discussion of causation, the negligence of each is a “but for” cause of the harm, even though they did not act together.
The traditional common law rule was-and still is in many cases today-that each tortfeasor in a case like Fermi’s is liable to the plaintiff for her full damages, since his negligence was a “but for” cause of the plaintiff’s injury. Courts generally refer to the defendants in such cases as “joint tortfeasors.” This is clearly loose language, though universally used. Fermi and Edison did not do anything “jointly,” in the sense that Kelvin and Curie did in the battery example, since they acted separately, without agreement. It is the resulting injury that is joint, not the actions of the defendants. The phrase “joint tortfeasors” simply means that the defendants both contributed to a single, indivisible injury to the plaintiff and are each fully liable for that injury.