Sources of procedural law in international dispute settlement

Despite the increasing diffusion of the international legal system, common patterns exist in the sources of procedural law governing various fora. These sources apply specifically and generally. The main specific sources are treaties, including constitutive instruments of dispute settlement bodies - such as the ICJ, ICSID, and WTO DSU - and other treaties like the New York Convention and the ICCPR. Rules adopted by dispute settlement bodies also prescribe procedure. Applicable sources are primarily found in Article 38(1)(b)-(d) of the ICJ Statute: customary international law, general principles of law, and ‘judicial decisions and the teachings of (…) publicists’. The authors find the latter two to be less problematic in practice than the first. Although controversial, dispute settlement bodies also possess inherent powers. Finally, whilst municipal laws are mere facts in international law - rather than binding norms - there nevertheless exists a symbiotic relationship between the two when it comes to procedural law.