Under the COMMON LAW, when an individual who had been injured by the wrongful acts of two or more persons acting in concert—known as joint tortfeasors—executed a release to one of the defendants, the releasor was regarded as having relinquished the claim against all the defendants, unless rights against them were clearly and specifically reserved in the release.
This rule proved to be unfair, however, because it forced the injured party to give up an entire claim against all tortfeasors without necessarily being totally compensated. Few jurisdictions still apply this rule. Most states currently permit a plaintiff to continue an action against the remaining joint tortfeasors after one of them has been released from liability unless the plaintiff has made an intentional surrender of the claim or has been totally compensated. An agreement of this type is called a COVENANT not to sue—the plaintiff does not give up the lawsuit but agrees not to enforce the claim against a particular joint tortfeasor although the others are still liable.