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 that the fact-finder assigns to the plaintiff for his or her own injury. For example, if a jury thinks that the plaintiff is 30% at fault for his own injury, 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 that the plaintiff's own negligence undermined his 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 his or her 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 his or her own negligence. Even if the plaintiff was negligent, the tortfeasor may still be held liable if he or she had the last clear chance to prevent the injury, meaning that 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