[New publication] The art of judicial inquiry: Exploring the ICJ’s questioning practice 

In a new book by T.M.C. Asser Press, author Karel Wellens (Radboud University Nijmegen) examines the International Court of Justice’s (ICJ) long-standing use of questioning during oral proceedings. He argues that judicial questions are not simply rhetorical tools but actively shape deliberations and outcomes in contentious cases.  

The modern ICJ hearing is no longer limited to scripted oral pleadings. Judges often step in with targeted questions that shape the direction of argument and provide the bench with clarifications that written submissions cannot always deliver. As the ICJ continues to play a key role in international disputes, understanding how these questions function has become increasingly important. 

In his new book “Question Time at the ICJ in Contentious Cases - A Functional Analysis of the Practice” (Asser Press/Springer), Wellens provides the first in-depth and comprehensive analysis of judicial questioning during oral proceedings at the ICJ, drawing on nearly eight decades of case law. 

The study shows how questions - whether conceptual, procedural or even hypothetical - can guide parties' litigation strategies, clarify complex issues and prove decisive in both judgments and individual opinions. Wellens demonstrates that questioning is not a minor part of the court's duties; in fact, it is now a key part of how the court manages its workload and makes its reasoning more legitimate. 

Questioning affects outcomes 

Rather than offering only theory, Wellens looks closely at how the ICJ functions on a daily basis. His survey of practice by judges and parties forms the basis for understanding how questioning affects outcomes and how it continues to influence the court’s case law. By examining how replies and comments have been taken into account in the court’s reasoning, Wellens demonstrates that questioning increases transparency, strengthens arguments and promotes a judicial dialogue that supports international adjudication. The study stresses that even relatively minor questions can later become central in judicial reasoning. Factors such as incidental proceedings, time limits and the provisional relevance of issues all play a role in shaping this exchange. 

Judicial dialogue 

The book links the court’s methods to broader themes in international law. The book shows that questions from the bench are not an end in themselves but a tool for managing proceedings and linking oral advocacy with judicial deliberation. Wellens explains how questioning helps to connect procedure with substance, and how it creates space for judicial dialogue that supports both fairness and clarity.
The author provides a clear framework for understanding how judicial questions connect procedural issues with substantive law, offering valuable insight into the court’s unique working culture. This makes the book not only a legal study but also a guide for understanding how the ICJ contributes to the development of international justice.  

A tool for managing proceedings 

 As the ICJ continues to play a key role in international disputes, this study provides timely and practical insights into the court’s methods. The practice-based approach brings theory and courtroom practice together, making the book a trusted reference for both scholars and practitioners. It highlights how judicial participation through inquiry supports efficiency as well as the development of international law, making this book a reliable resource for international lawyers, scholars, and practitioners involved in cases before the court.  

 About the author  

Karel Wellens is Emeritus Professor of International Law at Radboud University Nijmegen in the Netherlands. He is a seasoned academic who has written extensively about international adjudication and how courts and tribunals shape international law.  

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