Published online by Cambridge University Press: 19 June 2009
The theoretical separation of jus ad bellum and jus in bello provides important protection during armed conflict. It guarantees that jus in bello will apply regardless of the cause of a conflict. However, this distinction has been challenged by the view that in some cases a situation of self-defence may be so extreme, and the threat to the survival of the state so great, that violations of jus in bello may be warranted. The situation is compounded by the confusion of the principles of necessity and proportionality under jus ad bellum and jus in bello in both academic writing and the jurisprudence of international courts. The dangers of blurring the distinction will be elucidated by examining how jus ad bellum considerations have affected the application of jus in bello in armed conflicts between states and non-state actors.
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3 Hereinafter used interchangeably with the terms jus in bello, law of armed conflict, and laws of war.
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7 ICJ, Legality of the Threat or Use of Nuclear Weapons (Advisory Opinion), [1996] ICJ Rep. 226 (hereafter Nuclear Weapons case), para. 77.
8 Canizzaro, Enzo, ‘Contextualising proportionality: jus ad bellum and jus in bello in the Lebanese war’, International Review of the Red Cross, Vol. 88 (864) (2006), p. 791.CrossRefGoogle Scholar The principles of jus in bello can be traced back to practices of ancient civilizations. Modern jus in bello finds its sources in both customary and treaty law, including the Hague Conventions and Regulations, and the 1949 Geneva Conventions and their Additional Protocols (1977). On the other hand, modern jus ad bellum finds its origins in the 1919 Covenant of the League of Nations, the 1928 Kellog-Briand Pact and the UN Charter. See Malcolm Shaw, International Law, 4th edn, Cambridge University Press, Cambrudge, 1997, pp. 807–8. See also Gardam, Judith, ‘Proportionality and force in international law’, American Journal of International Law, Vol. 87 (1993), p. 391.CrossRefGoogle Scholar
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13 Ibid.
15 Hersch Lauterpacht, ‘Rules of warfare in an unlawful war’, in G. A. Lipsky (ed.), Law and Politics in the World Community (Essays on Hans Kelsen's Pure Theory and Related Problems in International Law), University of California Press, Berkeley, 1953.
16 Gardam, above note 8, p. 396.
17 Kolb, above note 12, p. 557.
18 He also distinguished a third category ‘Right after War’, which he describes as the obligation, rather, to establish peace. Immanuel Kant, The Philosophy of Law. An Exposition on the Fundamental Principles of Jurisprudence as the Science of Right, 1887, para. 53.
19 Gardam, above note 8, p. 397.
20 Kolb, above note 12, p. 557.
21 Additional Protocol I stipulates that the principles of international humanitarian law ‘must be applied in all circumstances to all persons who are protected by those instruments, without any adverse distinction based on the nature or origin of the armed conflict or on the causes espoused by or attributed to the Parties’. Protocol Additional to the Geneva Conventions of 12 August 1949 (Protocol I), International Legal Materials, Vol. 16, p. 1391.
22 The Preamble to Hague Convention IV stipulates that the Regulations are formulated with a view to ‘diminish[ing] the evils of war, so far as military requirements permit’, reflecting the pragmatic approach adopted in the codification of the laws of armed conflict. See 1907 Hague Convention IV Respecting the Laws and Customs of War on Land, 18 October 1907, in Roberts and Guelff (eds.), above note 6, p. 67.
23 See Lauterpacht, above note 15.
24 See Gardam, above note 8, p. 394.
25 Michael Walzer, Just and Unjust Wars. A Moral Argument with Historical Illustrations, Basic Books Classics, New York, 1997, p. 21.
26 Warner, Daniel, ‘The Nuclear Weapons Decision by the International Court of Justice: Locating the raison behind the raison d'état’, Millennium: Journal of International Studies, Vol. 25 (1998), p. 311.Google Scholar Although the aggressor may not be denied the right to rely on international humanitarian law during the war, this view is questionable in the area of the law of neutrality, and possibly belligerent rights after the cessation of hostilities (including acquisition of title over property, but not rights and duties in Occupation of a humanitarian character). See Lauterpacht, above note 15, pp. 104–10 and Greenwood, above note 9, p. 230.
27 Greenwood, above note 9, p. 222.
28 Ibid., p. 223.
29 Gardam, above note 8, p. 392.
30 See Christakis, Théodore, ‘De maximis non curat praetor? L'affaire de la licéité de la menace ou de l'emploi d'armes nucléaires’, Revue Hellénique de Droit International, Vol. 49 (1996), pp. 355–99.Google Scholar See also Weston, Burns, ‘Nuclear weapons and the World Court: ambiguity's consensus’, Transnational Law & Contemporary Problems, Vol. 7 (1997), p. 384.Google Scholar
31 Nuclear Weapons case, above note 7, para. 2E, dispositif.
32 For the first time in its history, each of the Court's judges drafted an individual opinion. Judges Guilllaume, Fleischhauer and Higgins and Vice-President Schwebel supported the view that recourse to nuclear weapons is lawful under certain conditions, whereas Judges Shahabuddeen, Weeramantry, Koroma, Ranjeva, Ferrari Bravo and Herczegh held it to be categorically unlawful.
33 Christakis, above note 30, p. 391. ‘The “snake-like” construction of the paragraph aims to leave the field open for endless interpretation games, with the hope that all possibilities will mutually exclude each other; the non-conclusion of the Court has the gift of changing forms at will, like the mythical Proteus!’ (author's translation).
34 Separate Opinion of Judge Fleischhauer, 35 ILM, p. 834, para. 4. The only other judge on the Court who seems to share a similar opinion is Judge Vereshchetin, who held that the Court was ‘debarred’ from finding a general rule of international humanitarian law that comprehensively proscribes recourse to nuclear weapons. See Declaration of Judge Vereshchetin, 35 ILM, p. 809, para. 2.
35 This is in sharp contrast to the view espoused by Higgins that, ‘in the present case, it is the physical survival of peoples that we must constantly have in view’. See Dissenting Opinion of Judge Higgins, 35 ILM, p. 934, para. 41.
36 Fleishchhauer, above note 34, para. 5.
37 Warner, above note 26, p. 311.
38 Ibid., p. 301.
39 Ibid. He further contends that the ‘right’ to state survival is a right that ‘has never been heard of before’.
40 Dissenting Opinion of Judge Koroma, 35 ILM, p. 926.
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43 Akande, Dapo, ‘Nuclear weapons, unclear law? Deciphering the Nuclear Weapons Advisory Opinion of the International Court’, British Yearbook of International Law, Vol. 68 (1997), p. 209.Google Scholar
44 Nuclear Weapons case, above note 7, para. 42. However, it also emphasized that the proportionality principle cannot rule out, a priori, any recourse to nuclear weapons.
45 Ibid., para. 86.
46 The Court was of the view that there was nothing in international law that prohibited nuclear weapons per se. The answer was thus to be found in the examination of these two bodies of law. Ibid., para. 36.
47 See Greenwood, Christopher, ‘The Advisory Opinion on nuclear weapons and the contribution of the International Court to international humanitarian law’, International Review of the Red Cross, No. 316 (1997), p. 65.CrossRefGoogle Scholar
48 ‘The use of nuclear weapons is … exceptionally difficult to reconcile with the rules of international law applicable in armed conflict …. But that is by no means to say that the use of nuclear weapons, in any and all circumstances, would necessarily and invariably conflict with those rules of international law. On the contrary, as the dispositif in effect acknowledges, while they might ‘generally’ do so, in specific cases they might not …'. Dissenting Opinion of Vice-President Schwebel, 35 ILM, p. 840.
49 Higgins, above note 35, para. 25.
50 Ibid., para. 28.
51 Ibid., para. 29.
52 Paragraph 90 set the stage for the controversy that resulted in the pronouncement of a non-liquet in paragraph 2E of the dispositif. The Court's pronouncement of a non liquet is itself a matter of much controversy. Does it imply that the conduct in question is acceptable (as per the Lotus principle)? According to Judge Higgins, rather than pronouncing a non liquet, the Court should have embraced the difficult task of weighing the competing legal claims against each other. Higgins, above note 35, para. 37–40. See also Falk, above note 41, p. 66.
53 It has also been argued that at least certain cardinal principles of international humanitarian law form part of jus cogens, such as the prohibition of means of warfare that have indiscriminate effects or cause unnecessary suffering. Separate Opinion of President Bedjaoui, [1996] ICJ Rep. 268 and 46, para. 21.
54 See Christakis, above note 30, p. 380.
55 This term leaves open many questions: ‘S'agit-il, comme on aurait automatiquement tendance à penser, d'une autre manière pour appeler les principes ‘impératifs', le jus cogens?’ Ibid. [Does it mean, as we automatically have the tendency to think, another way of naming the non-derogable principles of jus cogens?’ (author's translation)]
56 The Court is thus slipping into the dangerous territory of ‘relative normativity’. See Weil, Prosper, ‘Towards a relative normativity in international law?’, American Journal of International Law, Vol. 77 (1983), p. 413.CrossRefGoogle Scholar
57 Christakis, above note 30, p. 381.
58 However, Dominicé raises the important question as to ‘si le jus cogens reléve uniquement du droit des traités, ou si … il prohibe tous les actes matériel ou juridiques qui lui sont contraires’. See Christian Dominicé, ‘Application par la Cour Internationale de Justice’, in Les Nouvelles Frontières du Droit International Humanitaire, Institut d'études de droit international, Paris, 2003, pp. 81–8.
59 Ibid.
60 James Crawford, The International Law Commission's Articles on State Responsibility, Cambridge University Press, Cambridge, 2002, p. 166.
61 Ibid., p. 167.
62 Ibid., p. 166.
63 Marcelo G. Kohen, ‘The notion of state survival in international law’, in Laurence Boisson de Chazournes and Philippe Sands (eds.), International Law, the International Court of Justice and Nuclear Weapons, Cambridge University Press, Cambridge, p. 307.
64 It is important to distinguish between the concepts of necessity as a criminal defence, necessity as a situation precluding the wrongfulness of a state, and military necessity as the condition which allows a belligerent to derogate from the law of peace in order to achieve victory over the enemy. The latter is both an exception and a principle of limitation. See Weidenbaum, Paul, ‘Necessity in international law’, Transactions of the Grotius Society, Vol. 24 (1938), p. 113.Google Scholar
65 Crawford, above note 60, p. 185.
66 Commentary to Article 33 (Necessity) of 1996 Draft Articles on State Responsibility, in ILC Annual Report, 1996, para. 27.
67 Kohen, above note 63, p. 311.
68 Greenwood, above note 9, p. 231.
69 Nuclear Weapons case, above note 7, para. 42.
70 ICJ, Military and Paramilitary activities in and against Nicaragua (Nicaragua v. United States), Judgment, [1986] ICJ Rep., para. 194; Nuclear Weapons case, above note 7, para. 41.
71 Gardam, above note 8, p. 392.
72 Akande, above note 43, p. 191.
73 Gardam, above note 8, p. 404.
75 Canizzaro, above note 8, pp. 783–4.
76 However, it is possible that this infinite flexibility is both a strength and a weakness. See Gardam, above note 8, p. 412.
77 Akande, above note 43, p. 208.
78 Gardam, above note 8, p. 391.
79 API, Art. 51(5)(b).
80 Ibid., Art. 35(2).
82 Canizzaro, above note 8, p. 782.
83 Ibid., p. 781.
84 Christopher Greenwood, ‘Jus ad bellum and jus in bello in the Nuclear Weapons Advisory Opinion’, in Boisson de Chazournes and Sands, above note 63, p. 258.
85 Judith Gardam, ‘Necessity and Proportionality in jus ad bellum and jus in bello’, in Boisson de Chazournes and Sands, above note 63, p. 277.
86 Canizzaro, above note 8, p. 781.
87 Gardam, above note 8, pp. 404–05.
88 Ibid.
89 Walzer, above note 25.
90 Higgins, above note 35, para. 18.
91 Ibid., para. 21.
92 Ibid., para. 25.
93 Gardam, above note 8, p. 393.
94 Ibid., p. 404.
95 Ibid., p. 412.
96 Gardam, above note 85, p. 278.
97 Dunbar, N. C. H., ‘Military necessity in war crimes trials’, British Yearbook of International Law, Vol. 29 (1952), p. 443.Google Scholar
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100 See General Orders 100, Instructions for the Government of the Armies of the United States in the Field, Art. 14, available at www.yale.edu/lawweb/avalon/lieber.htm (last visited 25 August 2008).
101 Dunbar, above note 97, p. 444.
102 Weidenbaum, above note 64, p. 110.
103 Dunbar, above note 97, pp. 444–5. Although the doctrine of Kriegsraison was essentially non-binding, it was often invoked to circumvent legal obligations. Similar notions can be traced in the declarations of statesmen such as Rostow, who held that ‘[m]’ost states will sacrifice the law of armed conflict if the price of obedience is defeat or annihilation’, and Dean Acheson, who stated that ‘[l]’aw simply does not deal with such questions of ultimate power – power that comes close to the sources of sovereignty … No law can destroy the state creating the law. The survival of states is not a matter of law.’
104 Ibid., p. 446.
105 Weidenbaum, above note 64, pp. 110, 112–13.
106 Gardam, above note 85, p. 282.
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108 Dunbar, above note 97, p. 444.
109 USA v. Weizsäcker et al., quoted in Dunbar, above note 97, p. 446.
110 USA v. Alstötter et al., Law Reports of Trials of War Criminals, Vol. VI, United Nations War Crimes Commission, London, 1947–9, p. 52.
111 Ibid.
112 USA v. William List et al. (Case No. 7), Trials of War Criminals before the Nuernberg Military Tribunals, Vol. XI, 1950, p. 1247.
113 The Tribunal also stated that ‘whatever may be the cause of a war that has broken out, and whether or not the cause be a so-called just cause, the same rules of international law are valid as to what must not be done, may be done, and must be done by the belligerents themselves in making war against each other’. Ibid., pp. 1247–8.
114 Ibid., p. 1253. The plea of necessity was also rejected in the Peleus trial, which involved the murder of the unarmed crew of the sunken Allied ship Peleus under the orders of Heinz Eck, the commander of a German U-boat. In his summing up, the Judge Advocate affirmed that the prohibition of killing unarmed enemies was a fundamental usage of war. However, he added that circumstances might arise which would justify a belligerent's killing of an unarmed enemy person for the sake of preserving his own life, although no such circumstances arose in the present case. Because no judgment was delivered, it is unclear whether the Tribunal found any merit in this view. The Peleus Trial, Law Reports of Trials of War Criminals, Vol. I, pp. 11–12.
115 Ibid., p. 1255.
116 Ibid. Dunbar draws similar conclusions from the von Manstein trial, in which the Advocate-General stated that ‘the purpose of war is the overpowering of the enemy. The achievement of this purpose justifies any means including, in the case of necessity, the violation of the laws of war, if such violation will afford either the means to escape from imminent danger or the overpowering of the opponent.’ However, he advised that ‘the doctrine has no application to the laws of war except where the latter are actually qualified by explicit reference to military necessity’. Dunbar, above note 97, p. 445.
117 The scorched-earth policy involved the devastation of property and evacuation of inhabitants during the retreat of German forces. USA v. List, above note 112, p. 1113.
118 Ibid., pp. 1124–36, 1295–6.
119 Ibid., p. 1297 (emphasis added).
120 USA v. Krupp et al. (Case no. 10), Trials of War Criminals before the Nuernberg Military Tribunals, Vol. IX, pp. 1338–46.
121 Ibid., p. 1347.
122 USA v. Wilhelm von Leeb et al., Law Reports of Trials of War Criminals, Vol. 12, p. 124.
123 USA v. Wilhelm von Leeb et al., Trials of War Criminals before the Nuernberg Military Tribunals, Vol. XI, p. 541.
124 Ibid., p. 603.
125 Ibid., p. 541.
126 Schmitt, above note 107, p. 52.
127 In Tablada the Inter-American Commission on Human Rights stated that the law of armed conflict applies equally as between the parties (the Argentine government and the rebels), who both have the same duties under IHL. It also reaffirmed that ‘application of the law is not conditioned by the causes of the conflict’. See Report No. 55/97, Argentina, Doc. 38, 1997, paras. 173–174. Similarly, the Columbian Constitutional Court held that ‘the compulsory nature of IHL applies to all parties to an armed conflict, and not only to the armed forces of States which have ratified the relevant treaties … All armed individuals, whether or not they are part of a State force’, are under an obligation to respect those rules. See Columbia, Constitutional Conformity of Protocol II, Ruling No. C-225/95, para. 8.
128 Various parties abstained from voting on this provision as it was construed as ‘making the motives behind a conflict a criterion for the application of international humanitarian law’. See Declaration by the UK, VI, Official Records of the Diplomatic Conference on the Reaffirmation and Development of IHL Applicable in Armed Conflicts, Geneva, 1974–7, p. 46.
129 Final Report to the Prosecutor, in A. Klip and G. Sluiter (eds.), Annotated Leading Cases of International Criminal Tribunals, Intersentia, Oxford, 2003, p. 21.
130 Ibid.
131 Ibid.
132 ICTY, Prosecutor v. Dario Kordic and Mario Cerkez, IT-95-14/2, Judgement, 26 February 2001, para. 449.
133 ‘… A person shall not be criminally responsible if, at the time of that person's conduct: … (c) The person acts reasonably to defend himself or herself or another person or, in the case of war crimes, property which is essential for the survival of the person or another person or property which is essential for accomplishing a military mission against an imminent and unlawful use of force in a manner proportionate to the degree of danger to the person or the other person or property protected. The fact that the person was involved in a defensive operation conducted by forces shall not in itself constitute a ground for excluding criminal responsibility under this subparagraph.’ See 1998 Rome Statute of the International Criminal Court, in Roberts and Guelff, above note 6, p. 667.
134 Prosecutor v. Kordic, above note 132, p. 451.
135 Ibid., para. 344.
136 Ibid., para. 342.
137 ICTY, Prosecutor v. Tihomor Blaskic, IT-95-14-T, Judgement, 3 March 2000, para. 180.
138 ‘[T]he Appeals Chamber deems it necessary to rectify the Trial Chamber's statement, contained in paragraph 180 of the Trial Judgment, according to which “[t]argeting civilians or civilian property is an offence when not justified by military necessity”.’ It further underscored the absolute prohibition on the targeting of civilians in customary international law. See ICTY, Prosecutor v. Blaskic, IT-95-14-A, Appeals Chamber Judgement, 29 July 2004, para. 109.
139 Higgins, above note 35, para. 20; AP I, Art. 51 (2).
140 The ICTY's jurisprudence on wanton destruction of property is more consistent on this matter.
141 See Seto, Theodore, ‘The morality of terrorism’, Loyola of Los Angeles Law Review, Vol. 35 (2002), p. 1227.Google Scholar
142 A clear indication is the adoption of the Second Additional Protocol to the Geneva Conventions (1977), as well as the case law of the ICTY and ICTR.
143 See Human Rights Watch, ‘Troops in contact: air strikes and civilian deaths in Afghanistan’, 8 September 2008, available at http://hrw.org/reports/2008/afghanistan0908/ (last visited 12 October 2008).
144 See, for instance, Housing and Land Rights Network of the Habitat International Coalition and the World Organization against Torture, Joint Urgent Action Appeal, discussing Israel's policy of house demolitions in violation of international law for alleged reasons of self-defence. See also Amnesty International, ‘Colombia’, Amnesty International Report 2008, 2008, available at http://thereport.amnesty.org/eng/regions/americas/colombia (last visited 13 October 2008).
145 Bugnion, above note 10, p. 538.