Modern Considerations in the Identification of Customary International Law: Reflections on the ILC’ Reports (2013-2018) & Some International Judicial Decisions

Document Type : Original Article


1 Corresponding author,Assistant Professor of International Law, Bu-Ali Sina University, Iran. All websites accessed 3 July 2021

2 PhD Candidate in Public International Law, Seoul National University


International courts and tribunals, including the International Court of Justice (ICJ), have always played a crucial role in the process of identifying rules of customary international law (CIL). In this area, especially in recent decades, the approach that is employed as international jurisprudence has been modified because the principles of humanity and humanitarian law have evolved. Unlike the traditional approach that relies initially on the practice of states, this newly-emerged approach – which was also supported by the Special Rapporteur of the International Law Commission (ILC) in its fifth report in 2018 – seeks to identify opinio juris in the first place. What we have discussed in the present article is the necessity of the introduction of a new approach to the identification of customary rules in international law. For this purpose, we attempted to collect and analyze the concurring opinions and arguments that exist in judicial jurisprudence of various international tribunals such as the ICJ, as well as those of the ILC as ubiquitous evidence to establish a change in the process of the identification of custom.