to a person who consents"). In many cases, those engaging in risky activities will be asked to sign a waiver releasing another party from liability. For example, spectators to certain sports are assumed to accept a risk of injury, such as a hockey puck or baseball striking a member of the audience. Warnings by the defendant may also provide a defence depending upon the jurisdiction and circumstances. This issue arises, for example, in the duty of care that landowners have for guests or trespasses, known as occupiers' liability. Comparative or contributory negligence: If the victim has contributed to causing their own harm through negligent or irresponsible actions, the damages may be reduced or eliminated entirely. Contributory negligence: The English case Butterfield v. Forrester (1809) established this defence. In England, this "contributory negligence" became a partial defence, but in the United States, any fault by the victim completely eliminated any damages. This meant that if the plaintiff was 1% at fault, the victim would lose the entire lawsuit. This was viewed as unnecessarily harsh and therefore amended to a comparative negligence system in many states; as of 2007 contributory negligence exists in only a few states such as North Carolina and Maryland. Comparative negligence: In comparative negligence, the victim's damages are reduced according to the degree of fault. Comparative negligence has been criticised as allowing a plaintiff who is recklessly 95% negligent to recover 5% of the damages from the defendant. Economists have further criticised comparative negligence as not encouraging precaution under the calculus of negligence. In response, many states now have a 50% rule where the plaintiff recovers nothing if the plaintiff is more than 50% responsible. Illegality: If the claimant is involved in wrongdoing at the time the alleged negligence occurred, this may extinguish or reduce the defendant's liability. The legal maxim ex turpi causa non oritur actio, Latin for "no right of action arises from a despicable cause". Thus, if a burglar is verbally challenged by the property owner and sustains injury when jumping from a second story window to escape apprehension, there is no cause of action against the property owner even though that injury would not have been sustained but for the property owner's intervention. Other defences and immunities: Sovereign immunity Good Samaritan laws, especially in jurisdictions with a statutory or common law duty to rescue Charitable immunity Discovery in tort litigation Discovery (or disclosure), a