In some common law jurisdictions, contributory negligence is a defense to a tort claim based on negligence. If it is available, the defense completely bars plaintiffs from any recovery if they contribute to their own injury through their own negligence.
Because the contributory negligence doctrine can lead to harsh results, many common law jurisdictions have abolished it in favor of a "comparative fault" or "comparative negligence" approach. A comparative negligence approach reduces the plaintiff's damages award by the percentage of fault the fact-finder assigns to the plaintiff for their own injury. For example, if a jury thinks the plaintiff is 30% at fault, the plaintiff's damages award will be reduced by 30%.
History
The doctrine of contributory negligence was dominant in U.S. jurisprudence in the 19th and 20th century. The English case Butterfield v. Forrester is generally recognized as the first appearance, although in this case the judge held the plaintiff's own negligence undermined their argument that the defendant was the proximate cause of the injury. Whether contributory negligence is construed as negating proximate causation or as an affirmative defense, the effect is the same either way: the plaintiff's contributory negligence bars recovery.
Burden of proof
In some jurisdictions, in order to successfully raise a contributory negligence defense, the defendant must prove the negligence of a plaintiff or claimant. In others, the burden of proof is on a plaintiff to disprove their own negligence.
Even if the plaintiff was negligent, the tortfeasor may still be held liable if they had the last clear chance to prevent the injury, meaning even though the plaintiff was negligent the defendant was the last person with a clear opportunity to take action that would have prevented the plaintiff's injury from occurring.
Examples of contributory negligence
Example 1: A pedestrian crosses a road negligently and is hit by a driver who was driving negligently. Since the pedestrian has also contributed to the accident, they may be barred from complete and full recovery of damages from the driver (or their insurer) because the accident was less likely to occur if it hadn't been for their failure to keep a proper lookout.
Example 2: Another example of contributory negligence is where a plaintiff actively disregards warnings or fails to take reasonable steps for his or her safety, such as diving in shallow water without checking the depth first.
Pleading requirements
In some jurisdictions, such as United States federal courts, contributory negligence must be pleaded in the defendant's answer to the complaint as an affirmative defense. But in some jurisdictions it may be applied by the court in a tort matter irrespective of whether it was pleaded as a defense.
Availability
The contributory negligence defense is not available to a tortfeasor whose conduct rises above the level of ordinary negligence to intentional or malicious wrongdoing.
The classic version of contributory negligence, where a plaintiff who is even 0.01% negligent is barred from recovery, nowadays is referred to as "pure contributory negligence." Some states have adopted a "modified" or "mixed" version of contributory negligence where the plaintiff is only barred from recovery if he or she was more than a certain percentage at fault (typically, more than 50% at fault for their own injury).