Legality vs. Legitimacy: Can Uses of Force be Illegal but Justified?

Abstract

To many commentators, unilateral humanitarian intervention poses the dilemma of what states should do when there is a great divide between what international law requires and what morality dictates. Thiis issue was brought into sharp relief by NATO’s bombing campaign in Kosovo in 1999. Most western international lawyers concluded that NATO’s use of force was both morally justified and incompatible with international law. In short, NATO’s actions were ‘illegal but justified’. The ‘illegal but justified’ approach provides an intuitively attractive way of maintaining the prohibition on unilateral uses of force while permitting justice in individual cases. However, it is ultimately not a sustainable position given the role of state practice in developing international law. This approach also shifts the focus away from questions of legality and towards questions of legitimacy, which can undermine the law and risk manipulation.

Keywords: Kosovo, NATO, legality, legitimacy, illegal but justified, illegal but legitimate, use of force, intervention, Franck, Simma, mitigation, excuse, justification, Security Council, veto, spectrum