A comprehensive overview of legal defences in tort law, primarily focusing on how a defendant can reduce or eliminate liability for harm caused. Volenti Non Fit Injuria is explained as a complete defence, applying when a person knowingly and willingly accepts a risk, with case examples demonstrating the required elements of knowledge and voluntary consent, particularly noting exceptions for employees and rescuers. The text also details Contributory Negligence, which functions as a partial defence where the claimant's failure to take reasonable care contributes to their own injuries, resulting in a proportional reduction of damages, as illustrated by the Law Reform (Contributory Negligence) Act 1945 and relevant case law on seatbelts and intoxicated drivers. Finally, the complete defence of Illegality (Ex Turpi Causa Non Oritur Actio) is covered, preventing a claimant from recovering damages when the injury is closely linked to their own criminal conduct, although courts sometimes limit its application based on public policy.