Where two or more persons are liable in respect of the same liability, in most common law legal systems they may either be:

n. when two or more persons are both responsible for a debt, claim or judgment. It can be important to the person making the claim, as well as to a person who is sued, who can demand that anyone with joint liability for the alleged debt or claim for damages be joined in (brought into) the lawsuit. See also: joinder joint and several

n. two or more persons whose negligence in a single accident or event causes damages to another person. In many cases the joint tortfeasors are jointly and severally liable for the damages, meaning that any of them can be responsible to pay the entire amount, no matter how unequal the negligence of each party was. Example: Harry Hotrod is doing 90 miles an hour along a two-lane road in the early evening, Adele Aimster has stopped her car to study a map with her car sticking out into the lane by six inches. Hotrod swings out a couple of feet to miss Aimster's vehicle, never touches the brake, and hits Victor Victim, driving from the other direction, killing him. While Hotrod is grossly negligent for the high speed and failure to slow down, Aimster is also negligent for her car's slight intrusion into the lane. As a joint tortfeasor she may have to pay all the damages, particularly if Hotrod has no money or insurance. However, comparative negligence rules by statute or case law in most jurisdictions will apportion the liability by percentages of negligence among the tortfeasors (wrongdoers) and the injured parties. See also: comparative negligence negligence