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IDENTIFYING THE JUS COGENS NORM IN THE JUS AD BELLUM
Published online by Cambridge University Press: 08 January 2021
Abstract
This article argues that if there is a jus cogens norm in the jus ad bellum, it must be the customary norm which prohibits non-consensual uses of force that are neither validly authorised under the UN Charter nor lawful exercises of self-defence. In doing so this article will clarify the method by which jus cogens norms should be identified, based on a correct understanding and application of what it means for a norm to be ‘accepted and recognized as a norm from which no derogation is permitted’. It is argued that all existing jus cogens norms must be norms of customary law, and that the uncertainty regarding the scope of the jus cogens norm prohibiting force results from uncertainty as to the structure of the underlying customary and treaty law norms in the jus ad bellum.
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- Copyright © The Author(s) 2020. Published by Cambridge University Press for the British Institute of International and Comparative Law
Footnotes
I am grateful to Dapo Akande, Sachintha Dias, Adil Haque, Ulf Linderfalk, Federica Paddeu and the anonymous reviewers for comments on earlier drafts and helpful discussions of issues raised in the article. My research is funded by a UK Arts and Humanities Research Council studentship and a St Edmund Hall postgraduate scholarship.
References
1 Saul, M, ‘Identifying Jus Cogens Norms: The Interaction of Scholars and International Judges’ (2015) 5 AsianJIL 26CrossRefGoogle Scholar, 41. Danilenko notes that a ‘preoccupation with broad natural and moral foundations of jus cogens may explain the clear disregard of fundamental questions of legal form’ in Danilenko, GM, ‘International Jus Cogens: Issues of Law-Making’ (1991) 2 EJIL 42CrossRefGoogle Scholar, 44.
2 Saul (n 1) 43. For example, ‘the fact that a dispute relates to compliance with a norm having such a [jus cogens] character, which is assuredly the case with regard to the prohibition of genocide …’; Armed Activities on the Territory of the Congo (Democratic Republic of the Congo v Rwanda), Jurisdiction and Admissibility, Judgment, (2006) ICJ Rep 6, para 64.
3 See eg intervention by Mexico, ‘the prohibition of crimes against humanity was a long-standing jus cogens norm …’; UN GAOR, Sixth Committee, Summary Record of the 24th Meeting, UN Doc A/C.6/74/SR.25 (20 November 2019) para 11; intervention by United States of America, ‘Certainly, some of the items in the list were jus cogens norms, including most prominently the prohibition of genocide’; UN GAOR, Sixth Committee, Summary Record of the 24th Meeting, UN Doc A/C.6/74/SR.24 (11 November 2019) para 67.
4 Saul (n 1) 39.
5 ILC, Text of the draft conclusions on peremptory norms of general international law (jus cogens), adopted by the Commission on first reading with commentaries, ‘Report of the International Law Commission on the work of its seventy-first session’ A/74/10 (2019) 141, draft conclusion 23, commentary para 2.
6 See generally U Linderfalk, Understanding Jus Cogens in International Law and International Legal Discourse (Edward Elgar 2020); A Hameed, ‘Unravelling the Mystery of Jus Cogens in International Law’ (2014) 84(1) BYBIL 52, 61. Any generalisation will obscure important differences between individual positions, but one can broadly divide those writing about jus cogens into two groups. On the one hand, those who view jus cogens norms as arising due to their content: for example, the moral importance of the values they protect, see M Janis, ‘The Nature of Jus Cogens’ (1987–88) 3 ConnJIntlL 359; J Tasioulas, ‘In Defence of Relative Normativity: Communication Values and the Nicaragua Case’ (1996) 16 OJLS 85; ME O'Connell, ‘Jus Cogens: International Law's Higher Ethical Norms’ in DE Childress III (ed), The Role of Ethics in International Law (Cambridge University Press 2011). For a ‘public order’ view of jus cogens, see A Orakhelashvili, Peremptory Norms in International Law (Oxford University Press 2008) especially 30–1. On the other hand, those who consider the identification of a jus cogens norm to be independent of its content, and based rather on fulfilment of criteria established by the international legal system, see U Linderfalk, ‘The Emperor's New Clothes – What If No Jus Cogens Claim Can Be Justified?’ (2020) 22 ICLR 139, 140–1.
7 For example, Oscar Chinn Case, PCIJ A/B No 63 (1934), Separate Opinion Schücking, 149; Case No 10, United States v Krupp et al, Military Tribunal III, Nürnberg, Germany, 15 ILR 620 (31 July 1948).
8 E De Wet, ‘The Prohibition of Torture as an International Norm of Jus Cogens and Its Implications for National and Customary Law’ (2004) 15 EJIL 97, 103.
9 H Thirlway, The Sources of International Law (2nd edn, Oxford University Press 2019) 163; JA Green, ‘Questioning the Jus Cogens Status of the Prohibition of the Use of Force’ (2011) 32 MichJIntlL 215, 220. See, for example, Domingues v US, Inter-American Commission on Human Rights, Case 12.285, Report No 62/02 (22 October 2002) 50; Yusuf and Al Barakaat International Foundation v Council and Commission, European Court of Justice, Case T-306/01, (2005) ECR II-3533, para 278; Jones v Saudi Arabia (2006) UKHL 26 [42] (Lord Hoffmann).
10 ILC Draft Conclusions on jus cogens (n 5), draft conclusions 2 and 4.
11 Although the ILC includes ‘and which can be modified only by a subsequent norm of general international law having the same character’ in (b), the reference to modification is not generally considered to form part of the test for identification; CL Rozakis, The Concept of Jus Cogens in the Law of Treaties (North Holland 1976) 45–6.
12 ILC Draft Conclusions (n 5), draft conclusion 23, Annex, (a).
13 ILC, ‘Draft Articles on the Law of Treaties with Commentaries’ Yearbook of the International Law Commission, 1966, vol II, 187, draft Article 50, commentary para 1.
14 Case Concerning Oil Platforms (Islamic Republic of Iran v United States of America), Judgment, (2003) ICJ Rep 161, Separate Opinion Simma, para 9, although in the subsequent paragraph it seems he is referring only to the prohibition on the threat or use of force as jus cogens.
15 Oil Platforms, Memorial of Iran (8 June 1993) para 4.05.
16 Fisheries Jurisdiction (Spain v Canada), Jurisdiction of the Court, Memorial of Spain (28 September 1995) para 4.
17 Militarv and Paramilitary Activities in and against Nicaragua (Nicaragua v United States of America), Memorial of Nicaragua (Merits) (30 April 1985) para 213.
18 Legality of Use of Force (Serbia and Montenegro v United Kingdom), Preliminary Objections, Memorial of the Federal Republic of Yugoslavia (5 January 2000) para 2.1.1.
19 Fisheries Jurisdiction, Public Hearing of 17 June 1998, 10am, Submissions of Mr Hankey, Deputy Agent for Canada, para 14.
20 Although in its memorial Rwanda noted ‘that the norms codified in the substantive provisions of the [Genocide] Convention have the status of jus cogens’, Memorial of Rwanda, Armed Activities, para 3.17 (emphasis added), in its judgment the Court states rather that it is ‘assuredly the case’ that the ‘prohibition on genocide’ is of jus cogens character; Armed Activities (n 2) para 64.
21 The nature of legal exceptions is the subject of debate in the context of domestic law, in particular criminal law. On one view, an exception refers simply to conduct that falls outside the scope of a norm and is merely a linguistic construct—there is no difference between the exception, which sets out certain limits of the norm, and the norm itself. See G Williams ‘The Logic of Exceptions’ (1988) 47 CLJ 261, 278; R Dworkin, Taking Rights Seriously (Bloomsbury 2013) 41; RM Hare, ‘Principles’ (1972–73) 73 Proceedings of the Aristotelian Society 1, 6. Another view considers exceptions as separate norms external to the primary norm. For a very brief moment, even if only a sliver of time, the primary norm is applicable to the case which is then excepted by the separate norm creating the exception. See C Finkelstein ‘When the Rule Swallows the Exception’ in L Meyer (ed), Rules and Reasoning (Hart 1999) and M Carpentier, Norme et Exception – Essai sur la défaisabilité en droit (LGDJ 2014) 17. However, it is not necessary to analyse all apparent ‘exceptions’ using the same approach. Based on the context, nature and content of the particular norms in question, some exceptions may be better analysed as negative conditions of the primary norm, and others as a separate norm.
22 See Danilenko (n 1) 49. cf Orakhelashvili, who considers the possibility of jus cogens as an autonomous source of international law (n 6) 108–11; also Janis (n 6) 363. However, this appears to be a minority view, in addition to being inconsistent with the classic statement of the sources of international law in art 38(1) ICJ Statute.
23 As early as 1951 the prohibition was recognised by the ICJ as custom; Reservations to the Convention on the Prevention and Punishment of the Crime of Genocide, Advisory Opinion (1951) ICJ Rep 19, 23. The prohibition of genocide was stated to be a norm of jus cogens by Judge ad hoc Lauterpacht in 1993; Application of the Convention on the Prevention and Punishment of the Crime of Genocide, Provisional Measures, Order of 13 September 1993, (1993) ICJ Rep 325, Separate Opinion Lauterpacht, para 100.
24 The prohibition on torture was recognised by the ICJ as a norm of jus cogens in 2012 in Questions Relating to the Obligation to Prosecute or Extradite (Belgium v Senegal) Judgment (2012) ICJ Rep 422, 99. It had been recognised as custom by the ICTY Appeal Chamber in 2000, Prosecutor v Furundžija (IT-95-17/1), Appeals Chamber Judgment (21 July 2000) para 111.
25 Danilenko (n 1) 47.
26 Thirlway (n 9) 185–6.
27 L Alexidze, ‘Legal Nature of Jus Cogens in Contemporary International Law’ (1981) 172 Recueil des Cours 224, 255–6; Y Dinstein, War, Aggression and Self-Defense (6th edn, Cambridge University Press 2017) 109; or even a combination of different sources, K Wolfke ‘Jus Cogens in International Law (Regulation and Prospects)’ (1974) 6 PolishYBIntlL 145, 154–5; A Verdross, ‘Jus Dispositivum and Jus Cogens in International Law’ (1966) 60 AJIL 55, 61.
28 In its draft conclusions the ILC describes jus cogens norms as ‘universally applicable’, ILC, Draft conclusions on jus cogens (n 5), draft conclusion 3. Gaja has argued that the conception of jus cogens norms as universal seems ‘unjustifiably restricted’ due to its exclusion of the possibility of norms that are jus cogens within a restricted group of States, such as the Council of Europe; G Gaja, ‘Jus Cogens beyond the Vienna Convention’ (1981) 172 Recueil des Cours 275, 284. While there is nothing in principle to prevent a concept of regional jus cogens emerging, in practice the universality of jus cogens norms is now widely accepted and frequently acknowledged, and all those norms most commonly stated to be jus cogens are norms of general application. For example, US v Matta-Ballesteros, United States Court of Appeals, 9th Circuit, (1995) 71 F3d 754, 764 fn 5.
29 ILC, Draft Conclusions on Jus Cogens (n 5), draft conclusions 7(2) and 14(3).
30 Thirlway (n 9) 37; ‘It is well established that in its treaty relations a State cannot be bound without its consent’; Reservations to the Convention on Genocide (n 23) 21.
31 Separate Opinion Dugard, Armed Activities (n 2) para 6.
32 The Holy See and the State of Palestine are non-member State permanent observers to the UN. Kosovo and Taiwan are non-Members as their statehood remains contested. Switzerland remained a non-Member until 2002.
33 Danilenko (n 1) 63. The 1949 Geneva Conventions and the Convention on the Rights of the Child, both very widely ratified, are two exceptions. However, all contain denunciation clauses, and the provisions of the latter are not among those norms most commonly referred to as having jus cogens status; see, for example ILC, Draft Conclusions on jus cogens (n 5), draft conclusion 23, Annex. While the ‘basic rules of international humanitarian law’ are sometimes referred to as norms of jus cogens, the continued opposition of some States to the prohibition on belligerent reprisals casts doubt on such claims; see D Akande and S Shah ‘Immunities of State Officials, International Crimes, and Foreign Domestic Courts’ (2011) 21(4) EJIL 815, 833–4.
34 ILC Draft Articles on the Law of Treaties (n 13), draft Article 50, commentary para 4.
35 ILC, Draft Conclusions on jus cogens (n 5), draft conclusion 5.
36 ILC, Draft conclusions on jus cogens (n 5), draft conclusion 5, commentary para 9. The commentary to draft conclusion 13 (Absence of effect of reservations to treaties on peremptory norms of general international law (jus cogens)) also seems to assume that the treaty norm is not itself the source of the jus cogens norm: ‘while the reservation may well affect the treaty rule and the application of the treaty rule, the norm, as a peremptory norm of general international law (jus cogens), will not be affected’, para 2.
37 As the Commission said in 1966, it would ‘leave the full content of this rule [draft Article 50] to be worked out in State practice and in the jurisprudence of international tribunals’, ILC, Draft articles on the law of treaties (n 13), draft Article 50, commentary para 3.
38 I Brownlie, Principles of Public International Law (7th edn, Oxford University Press 2008) 510; L Hannikainen, Peremptory Norms (Jus Cogens) in International Lw (Helsinki 1988) 225; A de Hoogh ‘Jus Cogens and the Use of Armed Force’ in M Weller (ed), Oxford Handbook of the Use of Force in International Law (Oxford University Press 2015) 1163; U Linderfalk, ‘The Source of Jus Cogens Obligations – How Legal Positivism Copes with Peremptory International Law’ (2013) 82 NordicJIntL 369, 379.
39 M Byers, ‘Conceptualising the Relationship between Jus Cogens and Erga Omnes Rules’ (1997) 66 Nordic JIntlL 211, 228.
40 P Dumberry, ‘Incoherent and Ineffective: The Concept of Persistent Objector Revisited’ (2010) 59 ICLQ 779, 794.
41 Byers (n 39) 228.
42 Declaration on Principles of International Law Concerning Friendly Relations and Co-operation Between States in Accordance with the Charter of the United Nations, A/2625 (XXV) (24 October 1970) paras 1, 3.
43 Militarv and Paramilitary Activities in and against Nicaragua (Nicaragua v United States of America), Merits, Judgment, (1986) ICJ Rep 14, 188.
44 For example, M Bos, A Methodology of International Law (North Holland 1984) 246.
45 See Linderfalk (n 38) 378–9.
46 cf Linderfalk (n 38) 382–3.
47 This was the view of the Chair of the Drafting Committee at Vienna: ‘there was no question of requiring a rule to be accepted and recognised as jus cogens by all states. It would be enough that a very large majority did so; that would mean that if one state in isolation refused to accept the jus cogens character of a rule, or if that state was supported by a very small number of states, the acceptance and jus cogens character of the rule would not be affected’ quoted in Hannikainen (n 38) 210. Support for this view is widespread in doctrine, see Alexidze (n 27) 247; Dinstein (n 27) 109; Gaja (n 28) 283.
48 For example, Green (n 9) 243.
49 ILC, Draft conclusions on jus cogens (n 5), draft conclusion 4, commentary para 6.
50 G Abi-Saab, ‘Introduction’ The Concept of Jus Cogens in International Law, Lagonissi Conference: Papers and Proceedings, vol II (Carnegie 1967) 13; A Gómez-Robledo, ‘Le ius cogens international : sa genèse, sa nature, ses fonctions’ (1981) 172 Recueil des Cours 15, 112; T Ruys, ‘Armed Attack’ and Article 51 of the UN Charter (Cambridge University Press 2010) 25; D Costelloe, Legal Consequences of Peremptory Norms in International Law (Cambridge University Press 2017) 15; T Minagawa, ‘Essentiality and Reality of International Jus Cogens’ (1984) 2 HitotsubashiJL&Pol 1, 4; cf R Kolb, Théorie du Jus Cogens International (Geneva 2001), Titre I, section II, para 36.
51 As Schwelb wrote in 1967: ‘[Article 53] can be compared to a penal code which would provide that crimes shall be punished without saying which acts constitute crimes’; E Schwelb, ‘Some Aspects of International Jus Cogens as Formulated by the International Law Commission’ (1967) 61 AJIL 946, 964.
52 ILC, Draft conclusions on jus cogens (n 5), draft conclusion 8 and commentary.
53 For example, 1966 Report of the Sixth Committee, A/6547, 118, para 36; 1967 Report of the Sixth Committee, A/6955, 191, para 37; O Corten, Le droit contre la guerre (Pedone 2008) 300.
54 Corten (n 53) 297–8.
55 For example, UN Conference on the Law of Treaties, First Session, 52nd Meeting of the Committee of the Whole, para 18 (Evrigenis, Greece) para 31 (Mwendwa, Kenya).
56 UNGA Res A/RES/42/22 (18 November 1987).
57 See the statements of different delegations reported in UNGA ‘Report of the Special Committee on Enhancing the Effectiveness of the Principle of the Non-Use of Force in International Relations’ A/36/41 (1981) paras 37, 45, 57, 70, 130, 216; Corten (n 53) 301–6.
58 Corten (n 53) 295–303; also ST Helmerson ‘The Prohibition of the Use of Force as Jus Cogens: Explaining Apparent Derogations’ (2014) 61 NILR 167, 189.
59 Kolb (n 50), Titre I, section II, para 38.
60 R Kolb ‘Des problèmes conceptuels, systématiques et terminologiques en droit international public’ (2001) 56 ZföR 501, 505.
61 For example, two recent articles analysing the jus cogens prohibition derive (different) definitions of derogation from dictionaries: Helmerson (n 58) 175; P Butchard ‘Back to San Francisco: Explaining the Inherent Contradictions of Article 2(4) of the UN Charter’ (2018) JCSL 229, 239.
62 C Tomuschat, ‘Obligations Arising for States without or against Their Will’ (1993) 241 Recueil des Cours 203, 276.
63 J Sztucki, Jus Cogens and the Vienna Convention on the Law of Treaties (Springer 1974) 68; K Zemanek ‘How to Identify Peremptory Norms of International Law’ in P-M Dupuy (ed), Essays in Honour of Christian Tomuschat (2006 NP Engel) 1116: ‘sanctioning a factual violation is not the primary aim of the concept’.
64 Kolb (n 50) Titre I, Section II, para 47.
65 Alexidze (n 27) 233.
66 R Kolb, The Law of Treaties: An Introduction (2016 Elgar) 105; see also Zemanek's criticism of Kolb's thesis (n 63) 1109–12; A Orakhelashvili, ‘Changing Jus Cogens through State Practice? The Case of the Prohibition of the Use of Force and Its Exceptions’ in Weller (n 38) 157, 172, rejecting an African lex specialis in the jus ad bellum; Helmerson (n 58) 175–6.
67 Kolb (n 50) Titre I, Section I, para 13.
68 Rozakis (n 11) 22; Kolb (n 50) Titre I, section II, 51.
69 For example, ‘A general rule possesses a jus cogens character only when individual States are not permitted to derogate from the rule at all—not even by agreement in their mutual relations’ ILC, Fifth Report on the Law of Treaties by Sir Humphrey Waldock, Special Rapporteur, Observations and proposals of the Special Rapporteur, A/CN.4/183 and Add.1-4, 24 (emphasis added). Ragazzi interprets the inclusion of ‘even by’ as showing that ‘whereas the main focus in Article 53 is “derogation” in the strict sense, i.e. by treaty, the Commentary indicates a wider sense of the term “derogation”’; M Ragazzi, The Concept of International Obligations Erga Omnes (Oxford University Press 1997) 58.
70 De Hoogh (n 38) 1172.
71 U Linderfalk, ‘What Is So Special About Jus Cogens? – On the Difference between the Ordinary and the Peremptory International Law’ (2012) 14 ICLR 3, 12; also, for example, Green (n 9) 229.
72 ILC, Draft conclusions on jus cogens (n 5), draft conclusion 18.
73 Jurisdictional Immunities of the State (Germany v Italy), Judgment, (2012) ICJ Reps 99, para 93.
74 See also Prosecutor v Furundžija (IT-95-17/1-T) (10 December 1998), Trial Judgment, para 153: ‘the principle at issue cannot be derogated from by States through international treaties or local or special customs or even general customary rules not endowed with the same normative force’.
75 Separate Opinion Dugard, Armed Activities (n 2) para 6.
76 J Vidmar, ‘Rethinking jus cogens after Germany v Italy: Back to Article 53?’ (2013) 60 NILR 1, 25.
77 Immunities (n 73) para 95. cf Judge Cançado Trindade's criticism, Dissenting Opinion, paras 295–297.
78 Armed Activities (n 2) para 64.
79 Immunities (n 73) para 95.
80 S Talmon, ‘Jus Cogens after Germany v Italy: Substantive and Procedural Rules Distinguished’ (2012) LJIL 979, 986.
81 See Memorial of the Federal Republic of Germany (12 June 2009), Written Proceedings, Immunities, para 86.
82 Although note that Byers sees the jus cogens status of a particular norm as being entirely the result of customary processes; Byers (n 39) 221. In the commentary to draft conclusion 10 the ILC observes: ‘The fact that treaties have rarely been invalidated on account of conflict with peremptory norms is, however, not because the rule in article 53 is not accepted by States, but simply because States do not generally enter into treaties that conflict with peremptory norms of general international law (jus cogens)’, ILC, Draft conclusions on jus cogens (n 5), draft conclusion 10, commentary para 1.
83 Byers (n 39) 221.
84 Green (n 9) 229; Helmerson (n 58) 173.
85 Green (n 9) 229.
86 Green (n 9) 230, discussing Orakhelashvili.
87 See U Linderfalk ‘The Effect of Jus Cogens Norms: Whoever Opened Pandora's Box, Did You Ever Think About the Consequences?’ (2008) 18 EJIL 5 853, 867.
88 There are other difficulties with a jus cogens norm that includes the right of self-defence and collective security structure, such as the imposition of a time limit on that right by art 51 of the Charter, and the existence of Chapter VII of the Charter in treaty law only; see Butchard (n 61) 241–4; also Green (n 9) 230–2.
89 Green makes a similar argument but in relation to the treaty norm in art 2(4): its prohibition on force may be peremptory but not the prohibition on the threat of force (n 9) 228–9.
90 The Case of the SS Lotus (1927) PCIJ Series A No 10, 28; Colombian-Peruvian Asylum Case, Judgment, 20 November 1950, ICJ Rep (1950) 266, 277.
91 Costelloe (n 50) 17.
92 Rozakis (n 11) 74–6.
93 Dinstein (n 27) 114.
94 The relationship between Article 51 of the Charter and customary law is complex and lies beyond the scope of this article. For present purposes what matters is that Article 51 acts as an exception to Article 2(4) of the Charter only, not the customary prohibition.
95 Corfu Channel, Judgment of 9 April 1949, (1949) ICJ Rep 4, 35.
96 Nicaragua (n 43) para 176.
97 Provided certain conditions are met, it is widely accepted that a State may lawfully take actions that would otherwise amount to a violation of the prohibition on force, such as sending troops onto another State's territory, where the latter State has consented to that intervention. See, for example, International Law Association ‘Final Report on Aggression and the Use of Force’ (2018) 18–20. Although not stated explicitly, the Court's judgment in Armed Activities on the Territory of the Congo (Democratic Republic of the Congo v Uganda) clearly accepts that consent may render a use of force lawful; Judgment (2005) ICJ Rep 168, para 149.
98 Helmerson (n 58) 177–8; ILC, ‘Articles on the Responsibility of States for Internationally Wrongful Acts’ Yearbook of the International Law Commission (2001) vol II, Pt Two, art 26, commentary para 6.
99 FI Paddeu, ‘Military Assistance on Request and General Reasons against Force: Consent as a Justification for the Use of Force’ (2020) JUFIL.
100 See discussion by Helmerson (n 58) 182–6.
101 Butchard (n 61) 262–4; see also Helmerson (n 58) 176–7.
102 Orakhelashvili (n 6) 72; Kolb, R, Peremptory International Law Jus Cogens (Hart 2015) 98–9Google Scholar. See also Dinstein: the ‘built-in Charter exceptions frame the scope of application of the rule, whereas derogations “clash” with it’ (n 27) 111; Akande, D and Tzanakopoulos, A ‘The International Court of Justice and the Concept of Aggression’ in Kreß, C and Barriga, S (eds), The Crime of Aggression: A Commentary (Cambridge University Press 2017) 214Google Scholar fn 3; also, perhaps, Corten (n 53) 296, 609.
103 See Green (n 9) 232–4.
104 Green (n 9) 234.
105 Legal Consequences for States of the Continued Presence of South Africa in Namibia (South West Africa) notwithstanding Security Council Resolution 276 (1970), Advisory Opinion (21 June 1971), (1971) ICJ Rep 16, paras 21–22.
106 See the different possibilities suggested by Helmerson (n 58) 182–6.
107 Green (n 9) 237.
108 Green (n 9) 234–6.
109 cf Green (n 9) 241.