In a textbook case about one form of this concept, Knight sued Jewett for stepping on her hand in a game of touch football. The implied form of this concept is, in modern law, most commonly absorbed into comparative negligence. The express form of this concept may be negated if contrary to public policy. Typical evidence of the express form of this defense is a signed waiver. For 10 points, name this complete defense to negligence, which states that a plaintiff who knew of a particular hazard and still proceeded cannot 
In a textbook case about one form of this concept, Knight sued Jewett for stepping on her hand in a game of touch football. The implied form of this concept is, in modern law, most commonly absorbed into comparative negligence. The express form of this concept may be negated if contrary to public policy. Typical evidence of the express form of this defense is a signed waiver. For 10 points, name this complete defense to negligence, which states that a plaintiff who knew of a particular hazard and still proceeded cannot recover.
In a textbook case about one form of this concept, Knight sued Jewett for stepping on her hand in a game of touch football.
assumption of risk [accept word forms; prompt on waiver of risk before mentioned]