Abstract

In punishment, proportionality is the systematic mathematical relationship between the significance of the wrongdoing and the amount of punishment that may be imposed on the wrongdoer. In this chapter, Kershnar argues that there is no adequate equation for proportionality. The lack of an adequate equation rests on intuitions and the absence of a shared metric. If there is no equation for proportionality, then there is no proportionality. This is because if there is no equation for proportionality, then there is no general justification for proportionality. Purported justifications of punishment that lack proportionality—specifically, consequentialism and consent theory—are implausible. The lack of proportionality, then, is a threat to the notion that some punishment is justified and, more generally, non-consequentialism.