Often, the negligence of several people or entities combines to create a car crash. Suppose for example, there is roadwork that changes the texture of the road. The construction company and the city fail to give appropriate warnings. A drunk driver loses control of his vehicle on the changed road and swerves towards a fatigued driver, whose fatigue reduces his ability to respond to the car swerving towards him. On top of that, his car’s brakes are defective, so he crashes into the plaintiff.

Usually an experienced plaintiff’s attorney will investigate all possible causes of an accident and bring in all potentially responsible parties. This allows the plaintiff the greatest possibility of full recovery of his or her damages. A plaintiff in the example above may be able to sue the construction company, the city, the drunk driver, the fatigued driver, and the manufacturer of the brakes.

A plaintiff bringing a lawsuit after a car crash has only one opportunity to obtain compensation for any injuries. If a victim sues only one party when there are multiple responsible parties, he or she has lost the opportunity to bring a suit against the other responsible parties.

In the example above, the jury will apportion fault among all parties found to be responsible. Often, one or more defendants will use the defense that the plaintiff is partially at fault. In those cases, the jury will also evaluate the plaintiff’s culpability. If the total award is $100,000, and the city is 10% at fault, the construction company is 20% at fault, the drunk driver is 40% at fault, the fatigued driver is 20% at fault, the manufacturer is 10% at fault, and the plaintiff is 0% at fault, the plaintiff will be able to recover all of his or her damages from the other parties.

Many states follow the doctrine of joint and several liability. Multiple defendants are jointly and severally liable if their concurrent acts brought about an injury to the victim. This doctrine allows a plaintiff to recover the full value of a judgment from any party deemed to be at fault, even if that party is much less at fault than the other defendants. That party can then seek contribution from the others found to be at fault.

If the example above takes place in a state that permits joint and several liability, the plaintiff can collect the full $100,000 from the construction company. The construction company can try to demand contribution from the other at-fault defendants. However, if the drunk driver and the fatigued driver are uninsured, the construction company will only be able to collect contributions from the city and the manufacturer. The goal of joint and several liability is to account for the possibility that one or more defendants are judgment-proof by shifting this risk to others at fault for the accident.

Some states do not follow the doctrine of joint and several liability. They only permit a plaintiff to recover from any defendant the percentage of the damages for which that defendant is held responsible.