This chapter explores the sensitive topic of police violence at political protests in Ireland in more recent times and in particular the question of when and how it is legitimised. Long experience of discussing the matter with students, colleagues, journalists and members of the public makes it clear that many people see police acts using force as per se legitimate and therefore not ‘violent’, a term thus reserved for illegitimate acts. Yet police behaviour can be contested publicly and on occasion found to be illegitimate (by expert opinion, by media commentators, by internal inquiries or indeed by courts of law). The question of how the use of force is legitimised – and what conditions make this achievement of legitimacy more or less likely – is then an interesting one, as is the broader question of why a police decision is made to use force in the first place, and at what level.