There is a moral presumption against the possession or exercise of coercive power, but political power is coercive. If we think that political power is sometimes morally justified, then given the moral presumption against coercive power, we need a theory as to when political power is morally justified and what justifies it. That is, we need a theory of political legitimacy. This dissertation develops and defends a novel theory of legitimacy, the Act-Focused Consequentialist Theory of Legitimacy. This theory departs in significant respects from existing theories. In Part One of the dissertation, “Four Theses on Legitimacy,” I argue that these departures are well-motivated given the shortcomings of these existing theories. I object that these...