Policing by consent is an influential frame of reference for police forces, policy makers, and members of the public in appraising the means and ends of law enforcement in Anglo-American societies. The doctrine is nonetheless vulnerable to powerful philosophical and political objections, which suggests that an alternative paradigm is necessary. This article draws on recent republican political theory in elaborating a doctrine of policing by contestation. This republican conception does not rest the legitimacy of policing on the supposed consent of the policed, but on the availability and adequacy of the means through which the policed can contest arbitrary interference at the hands of the police.