Keeping Hands Clean in War: The Double-Effect Approach to Killing

This paper compares two approaches to the moral justifications for killing in war: the forfeiture approach, which sees killing as justified when the victim has forfeited his or her right not to be killed, and the double-effect approach, which argues that even if intentional killing is absolutely prohibited, that killing can still be morally acceptable under certain conditions, most notably if it is not the intended, desired outcome of a person’s chosen action. The double-effect approach is considered out of fashion in contemporary military ethical literate. I argue that it warrants equal attention as an internally viable and coherent account of the morality of killing, and is preferable in at least one way: that it protects combatants from being necessarily culpable of killing merely by serving in active combat positions.

By defending an alternate framework to the forfeiture approach to killing which is most popular in today’s military ethical literature, I provide an opportunity for new and increased philosophical reflection and discourse on the ethics of killing, as well as new opportunity for defenders of double-effect to make a substantive contribution to the field. This paper demonstrates the internal consistency of arguments that seek to utilise DDE, including its relevance to individual self-defence and individual killing in war.