Peremptory Norms in International Law (Oxford Monographs in International Law)

## Abstract This monograph analyses the questions raised by the legal effects of peremptory norms of international law (jus cogens), reflected in Article 53 of the 1969 Vienna Convention on the Law of Treaties. A comprehensive study of this problem has been lacking so far in international legal doctrine. Peremptory norms, although often criticised and even more often approached with sceptical nihilism, nevertheless attract growing doctrinal and practical attention, and have increasing importance in determining the permissible limits on the action of State and non-State actors in different areas. In view of this overriding impact on what might otherwise be instances of the law-making process, peremptory norms concern a constitutional aspect of international law. Peremptory norms are non-derogable norms, and the concept of derogation is among the key concepts analysed here. Derogation from peremptory norms can be attempted in a wide variety of situations, but if peremptory norms are to operate as norms and not merely as aspirations, they must generate consequences that are also peremptory. This effects-oriented character of peremptory norms is examined in a variety of fields. The hierarchical superiority of peremptory norms is not limited to the sphere of primary legal relations, but becomes most crucially relevant after a specific peremptory norm is breached. A norm's peremptory character is relevant not only for its substance but also for its consequences; peremptoriness consists primarily in the capacity to impact through its effects upon conflicting acts, situations and agreements. This monograph analyzes the questions raised by the legal effects of peremptory norms of international law ( jus cogens ). A comprehensive study of this problem has been lacking so far in international legal doctrine. Peremptory norms, although often criticized and even more often approached with skeptical nihilism, nevertheless attract growing doctrinal and practical attention and have increasing importance in determining the permissible limits on the action of State and non-State actors in different areas. In view of this overriding impact on what might otherwise be instances of the law-making process, peremptory norms concern a constitutional aspect of international law. Peremptory norms are non-derogable norms, and the concept of derogation is among the key concepts analyzed here. Derogation from peremptory norms can be attempted in a wide variety of situations, but if peremptory norms are to operate as norms and not merely as aspirations they must generate consequences that are also peremptory. This effects-oriented character of peremptory norms is examined in a variety of fields. Despite the growing relevance of peremptory norms in practice, doctrine has failed to treat the issue comprehensively and has often been limited to examining specific aspects of the problem, such as the impact of peremptory norms in the law of treaties. This fresh effort to examine and explain the phenomenon of peremptory norms in key areas fills an important doctrinal gap through presenting in a systematic way the effects of peremptory norms and reappraising the significance of such effects, bearing in mind their overall nature. It also demonstrates that the hierarchical superiority of peremptory norms is not limited to the sphere of primary legal relations but becomes most crucially relevant after a specific peremptory norm is breached. A norm's peremptory character is relevant not only for its substance but also for its consequences; peremptoriness consists primarily in the capacity to impact through its effects upon conflicting acts, situations and agreements. Peremptory norms as international public order The identification of peremptory norms Distinctive characteristics of peremptory norms Concepts cognate to jus cogens Sources and modification of peremptory norms The effect of jus cogens in the law of treaties Peremptory norms and the validity of the actions of states Remedies for breaches of peremptory norms Peremptory norms and the allocation of jurisdiction to states Peremptory norms and state immunity Problems of subsequent validation of breaches of jus cogens The nature and scope of jus cogens limitations on the Security Council's powers The normative conflict between a Security Council resolution and jus cogens: the practice of the Security Council Legal consequences of the conflict of a security council resolution with peremptory norms Peremptory norms and international judicial jurisdiction Jus cogens and the standing to bring judicial claims The impact of jus cogens on friendly settlement and discontinuance of cases Techniques of interaction of international jus cogens with national law Peremptory norms and acts of foreign states in private international law 561 Conclusion. Peremptory norms are non-derogable standards of international law which impose basic limits on how far governments, politicians, and diplomats can further their own goals. For example, certain core norms prohibit aggressive war and protect basic human rights. This is the first thorough examination of the theory and application of these norms. Peremptory norms are non-derogable standards of international public policy which impose limits on how far governments politicians and diplomats can further their own goals in making international transactions. This work examines their increasing importance in determining the permissible limits on the actions of State actors.