Resultant moral luck and the scope of moral responsibility

Resultant moral luck occurs whenever aspects of an agent's moral responsibility are affected by luck pertaining to the outcomes of their actions. Many authors reject the existence of moral luck in this sense, but they do so in different ways. Michael Zimmerman argues that resultant luck affects the scope of moral responsibility, but not its degree. That is, it affects what agents are responsible for, but not how responsible they are. Andrew Khoury takes a more resolute approach, arguing that both the scope and the degree of moral responsibility are free from resultant luck. In this paper, I criticize both accounts and develop an alternative. I argue, first, that Khoury's approach leads to an implausibly far-reaching error-theory about moral responsibility. Second, Zimmerman's account cannot account for all the ways in which moral responsibility comes in degrees. Third, these problems can be overcome by introducing a distinction between two concepts of responsibility that both come with scope and degree. The first concept I call internal responsibility, as it applies exclusively to agent-internal factors. The second concept I call external responsibility, as it applies to (partly) agent-external factors such as actions and their outcomes. Given this distinction, we can avoid the problems of Khoury's as well as Zimmerman's accounts while preserving the central intuition behind the rejection of resultant moral luck.