Legal Consequences of Breaches of Peremptory Norms in the ICJ’s Advisory Opinions: Jus Cogens or Erga Omnes?

Luciano Pezzano

doi:10.21697/2026.15.1.02

Opublikowane: 2026-06-26

Tom 15 Nr 1 (2026)

Legal Consequences of Breaches of Peremptory Norms in the ICJ’s Advisory Opinions: Jus Cogens or Erga Omnes?

Luciano Pezzano

Polish Review of International and European Law

Dział: Studies

https://doi.org/10.21697/2026.15.1.02

Abstrakt

Article 41 ARSIWA enshrines three duties for all States in case of a serious breach of an obligation arising from a peremptory norm (‘jus cogens duties’). However, since 2004, the ICJ has ascribed these duties to breaches of obligations erga omnes, in its advisory opinions of the Wall, Chagos and Palestine. It seems that the ICJ considers that such duties are consequences of the breaches of obligations erga omnes, and not of jus cogens norms, which could imply a sort of confusion between both concepts. However, as the ILC stressed, given the significant overlap between jus cogens and obligations erga omnes, the deduction that the ICJ in these decisions was referring (implicitly) to peremptory norms is not unwarranted. This contribution aims to offer a review of the determination by the ICJ of jus cogens duties in its advisory opinions, and the seeming confusion with obligations erga omnes – and the criticism regarding it – arguing for a way of interpretation that avoids that confusion. The study allows confirming the ILC’s deduction, and it stresses the importance of the 2025 advisory opinion on Climate Change to that end.

Słowa kluczowe:

jus cogens norms, obligations erga omnes, international responsibility, International Court of Justice, advisory opinions

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Zasady cytowania

Pezzano, L. (2026). Legal Consequences of Breaches of Peremptory Norms in the ICJ’s Advisory Opinions: Jus Cogens or Erga Omnes?. Polish Review of International and European Law, 15(1), 49–82. https://doi.org/10.21697/2026.15.1.02

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Utwór dostępny jest na licencji Creative Commons Uznanie autorstwa – Bez utworów zależnych 4.0 Międzynarodowe.

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