Evaluating Wrongness Constraints on Criminalisation

Some claim that criminalisation is morally permissible only when the conduct criminalised is morally wrong. This claim can be disambiguated into at least three principles which differ according to whether, and how, wrongness is dependent on details of the law: the strong constraint, the moderate constraint, and the weak constraint. In this paper I argue that the weak wrongness constraint is preferable to the strong and moderate constraints. That is, we should prefer the view that conduct criminalised must be morally wrong, but qualifying wrongness can depend on criminalising the conduct first. Further, I will show that my arguments in support of the weak wrongness constraint have wider implications. Favouring the weak wrongness constraint implies that condemning wrongs cannot be the only legitimate reason in favour of criminalisation. Those who think condemnation can justify criminalisation should be pluralists.