International humanitarian law

Introduction This chapter considers the evolution of international legal positivism in the context of international humanitarian law (IHL). It espouses an understanding of ‘legal positivism’ as unity of sources, recognising as law only those norms which are generated by a pre-set legal procedure, independent of any inherent value. It is thus closely connected to, although not identical to, the notion of formalism, understood here as the identification of norms through formal criteria. Modern-day laws of armed conflict present an important critique to the traditional positivist sources doctrine. It is often contended that if state practice on the battlefield is the yardstick to be used to identify rules of IHL, then IHL is in a precarious state, given the prevalence of practice contrary to alleged prohibitions, which puts into doubt the existence of law in the first place, or, where the law had been established, suggests that it has been modified. In addition, it is said that positivist approaches to the sources of IHL hamper its ability to address contemporary realities and challenges, such as the massive involvement of non-state actors in armed conflicts. Classical doctrines on sources of law, as described below, thus encounter difficulties in conceptualising IHL in a manner which retains the latter’s legitimacy. This chapter evaluates these claims in light of developments in the theory of sources and in its application specifically to IHL.