There’s a widespread intuition that if the only way an innocent person can stop her villainous attacker from killing her is to kill him instead, then she is morally permitted to do so. But why is it that she is permitted to employ lethal force on an aggressor if that is what is required to save her life? My primary goal in this paper is to defend David Rodin's fairly recent and under-recognized account of self-defense that answers this question. There are roughly two kinds of non-consequentialist accounts of self-defense:'forced-choice' accounts and 'rights-based' accounts. I first examine what I take to be the most plausible 'forced-choice' account of self-defense and I argue that it is unable to withstand two recent criticisms. I then proceed to adjudicate between two prominent 'rights-based' accounts of self-defense: call them the Thomson/Uniacke account and the Rodinian account. Any rights-based account of self-defense must explain how it is that X, who villainously tries to kill Y, forfeits his right to life. I argue both that Thomson/Uniacke's explanation cannot account for the clear permissibility of killing a certain kind of aggressor in self-defense, and
that the attempts that could be made to account for this permissibility are either ad-hoc or permit the killing of persons that are morally on par with innocent bystanders. I point out how Thomson/Uniacke can evade the seeming difficulties that I raise by only permitting lethal defensive force against culpable aggressors. But allowing defensive force to be employed only on the culpable goes against one of their central tenets. I then discuss the Rodinian account, how it evades the criticisms I raise, as well as its other virtues. I conclude that while it has difficulties of its own, it is the more plausible one to adopt.