Due Diligence and the Recent Advisory Opinions of the International Court of Justice (2025) and the International Tribunal for the Law of the Sea (2024)

Document Type : Original Article

Author

Assistant Professor of International Law, Faculty of Literature and Humanities, University of Neyshabur, Neyshabur, Iran.

10.22091/cpl.2026.14555.1082

Abstract

The recognition of environmental vulnerability and the inadequacy of state responsibility for damages resulting from wrongful acts, or the imposition of strict liability, are among the realities that necessitated the emergence of the due diligence framework. Notwithstanding the widespread invocation of this concept across various domains of international law, significant ambiguities persist regarding the juridical nature, sources, and regime of due diligence. The International Tribunal for the Law of the Sea (ITLOS) and the International Court of Justice (ICJ) have articulated invaluable insights concerning this concept in their 2024 and 2025 advisory opinions, the explanation and analysis of which constitute the subject of this article. Utilizing library-based resources and a doctrinal research method grounded in a positivist and comparative approach, this paper reflects the findings of these tribunals regarding the standard of conduct inherent in due diligence, the mutability of its content, and the determinants thereof. It concludes that while the proliferation of judicial bodies was once perceived as a factor in the fragmentation of international law, these institutions now provide mutual reinforcement, thereby ensuring the integrity and coherence of international legal norms in the sphere of climate change.

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References

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References
Books
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International Tribunal for the Law of the Sea (ITLOS)
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Journal of Comparative Public Law
Volume 2, Issue 3 - Serial Number 7
November 2025
Pages 26-54

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