The international law-making capacity of non-State actors. Revisiting the fundamentals of the international law-making process under Customary International Humanitarian Law.

Today we see a fundamental crisis in the creation of customary international law (CIL), non-written norms of international law. Traditionally, under general international law the capacity to make CIL is reserved to States and, to a lesser extent, to international organizations. This view does not account for the rising importance of non-State actors (NSAs) such as NGOs and armed groups, under international law. This affects the legitimacy of CIL. Especially in the law of armed conflict, international humanitarian law (IHL), debates arise. After all, under IHL both non-State armed groups (NSAGs) and States have rights and obligations. In addition, the International Committee of the Red Cross (ICRC), a non-state body, has been mandated to provide advice on IHL and prepare any development of this law. However, the role of NSAGs and the ICRC in the making of customary IHL is unclear. This causes an asymmetry between how IHL treats States and NSAs and how the traditional doctrine of CIL does not attribute them any lawmaking capacities. My research carries out a fundamental and critical inquiry into the making of CIL in one particular field of international law, IHL. Starting from the theory of interactional international law-making, I revisit lawmaking under customary IHL to review the role of NSAs. Based on a fundamental legal review of lawmaking in customary IHL, I will propose a theory which aims to complement the traditional view of CIL and strengthen its legitimacy.