The role of judicial institutions in the development of international law has been an open question since the days of the Permanent Court of International Justice. Already in 1934, Hersch Lauterpacht had advanced the claim that ‘judicial law-making is a permanent feature of the administration of justice in every society’. In many respects, if the adjective ‘judicial’ can be used as pertaining to a court of law or a system of courts of law that are dedicated to the administration of justice within a legal order, understanding a judiciary’s role in law-making remains a foundational question as to the nature and form of a legal system.