Patrick Tomlin

In this chapter we introduce the nascent literature on Moral Uncertainty Theory and explore its application to the criminal law. Moral Uncertainty Theory seeks to address the question of what we ought to do when we are uncertain about what to do because we are torn between rival moral theories. For instance, we may have some credence in one theory that tells us to do A but also in another that tells us to do B. We examine how we might decide whether or not to criminalize some conduct when we are unsure as to whether or not the conduct is morally permitted and whether or not it is permissible to criminalize the conduct. We also look at how we might make sentencing decisions under moral uncertainty. We argue that Moral Uncertainty Theory can be an illuminating way to address these questions but find that doing so is a lot more complicated than applying Moral Uncertainty Theory to individual conduct.

The individualist nature of much contemporary just war theory means that we often discuss cases with single attackers. But even if war is best understood in this individualist way, in war combatants often have to make decisions about how to distribute harms among a plurality of aggressors: they must decide whom and how many to harm, and how much to harm them. In this paper, I look at simultaneous multiple aggressor cases in which more than one distribution of harm among aggressors is available. I show how such cases pose deep questions concerning the nature, role, and scope of the necessity principle, and its relationship to both liability and narrow proportionality. I argue that a hitherto unrecognised measure – ‘narrow proportionality shortfall’ – and its distribution is relevant in choosing how to distribute harms across aggressors. I then extend this analysis to show how this may help us with a puzzle concerning sequential attacks.