The Possibilities and Legitimacy of Non-State Participation in the Formation of Customary Law

Non-state actors can contribute to shaping customary law indirectly, through inspiration and pressure, or formally when so empowered by States. Decisions on granting non-state actors customary law-making capacities must be critically decided on a case-by-case basis, in light of the legal interests at stake, risks of making regulation subservient to their interests, and legitimacy and effectiveness considerations. Since non-state involvement in the formation or change of customary law is not limited to direct law-making capacities, different strategies can be used to both receive their input and promote their acceptance of and respect of customary law. Internal and international democratization of State decisions and collective law-making are essential if the (currently) mostly-State-centric system of custom determination is to be fair. This demands a duty to examine non-state proposals in good faith.