Introduction

The International Court of Justice and the International Law Commission have each significantly contributed to the development of international law. While the Court and the Commission may rival each other in their importance for international law, as Sir Robert Jennings once famously said, it is a constructive and fruitful rivalry of two United Nations organs with distinct but mutually enriching functions.

The Court pronounces only on those issues brought before it by States consenting to its jurisdiction, or by United Nations organs and agencies requesting advisory opinions. A decision of the Court is given within the confines of a specific dispute between the parties and is binding on those parties alone. The Commission, on the other hand, is free – with due regard to the views of the General Assembly – to choose the subjects of its study: those areas in which the law is in particular need of clarification, codification or progressive development. The Commission can set the parameters of how that study will be conducted, often over the course of many years. The Commission's deliberations involve a wide-ranging scholarly and systematic analysis of state practice, and of the jurisprudence of international tribunals and academic doctrine, in order to distill and develop the applicable legal principles.