Separate opinions of judges as a factor in the development of international law: between doctrine and judicial practice

Abstract

This article examines the role of individual (separate) judicial opinions in the development of international law. It analyses their functional significance in the practice of international judicial bodies, in particular the International Court of Justice, the International Criminal Tribunal for the former Yugoslavia, and the International Tribunal for the Law of the Sea. It is established that, despite lacking formal status as a source of international law, separate opinions are capable of exerting a substantial influence on the formation and transformation of legal approaches.

The study argues that the influence of separate opinions is most significant in situations of doctrinal disagreement among judges, as well as in cases where legal norms are at an early stage of development. It is demonstrated that in such contexts, separate opinions may serve as conceptual reference points for subsequent judicial practice, transforming from minority positions into dominant approaches. Particular attention is paid to the inter-institutional influence of separate opinions, manifested in the borrowing of legal reasoning by different international judicial bodies. It is emphasized that such influence contributes to the coherence of international judicial practice and strengthens the unity of legal standards. At the same time, it is shown that separate opinions may act as catalysts for the reconsideration of established approaches, even in the absence of their explicit citation in subsequent decisions.

Based on an analysis of case law, the article identifies mechanisms of implicit integration of separate opinions into judicial decisions, as well as their role in shaping new legal standards, particularly in matters of state responsibility attribution, defining elements of international crimes, interpretation of the United Nations Convention on the Law of the Sea, and the application of the plausibility test in provisional measures proceedings.

The article concludes that separate judicial opinions should be regarded as an important element of doctrinal influence in international law, contributing to its evolutionary development, flexibility, and capacity to adapt to emerging challenges. They function as a form of judicial dialogue both among judges and across international judicial institutions, facilitating the development of consistent and coherent jurisprudence.