In this novel approach to understanding consent, Jill D. Weinberg presents two case studies of activities in which participants engage in violent acts: competitive mixed martial arts (MMA) and sexual sadism and masochism (BDSM). Participants in both cases assent to injury and thereby engage in a form of social decriminalization, using the language of consent to render their actions legally and socially tolerable. Yet, these activities are treated differently under criminal battery law: sports,...