Deontological Constraints and the Doctrine of Double Effect

A defining feature of deontological ethics, distinguishing it sharply from consequentialism, is its commitment to agent-relative constraints: moral requirements not to perform certain kinds of action, such as killing an innocent person, that bind an agent even when violating the constraint would produce a better overall outcome, including preventing a greater number of comparable violations by others. Where a consequentialist evaluates options solely by their aggregate results, a deontologist typically holds that some acts are forbidden to the agent regardless of consequences, generating the characteristic deontological asymmetry between doing harm and merely allowing harm to occur, and between intending harm as a means or an end and merely foreseeing harm as a side effect.