Making Harm Necessary: an essay on Punishment and Self-defence

For harm to be permissible, it must be necessary. This principle is widely endorsed in a range of contexts. But sometimes how much harm it is necessary for an agent to inflict is the result of the conduct or dispositions of others. Let’s call these third parties “necessity-makers.” This article explores the moral implications of necessity-making, arguing that necessity-makers can be liable to harm and that this has important ramifications for deterrent punishment in particular. I also argue that aggressors are sometimes only partially liable to the harm made necessary, requiring us to rethink the relationship between necessity and liability.