1 There is no clear-cut definition of peace operations in public international law. The terms ‘peace operations’, ‘peace-support operations’, ‘peacekeeping operations’ or ‘peace-enforcement operations’ do not appear in the UN Charter. They may be interpreted in various ways (see, for example, United Nations Peacekeeping Operations: Principles and Guidelines, United Nations, New York, 2008) and are sometimes used interchangeably. For a comprehensive analysis of the definition of peace operations, see Marten Zwanenburg, Accountability of Peace Support Operations, Martinus Nijhoff Publishers, 2005, pp. 11–50.

For the purposes of this article, the term ‘peace operations’ covers both peacekeeping and peace-enforcement operations conducted by international organisations, regional organisations or coalitions of states acting on behalf of the international community in pursuance of a UN Security Council resolution adopted under Chapters VI, VII or VIII of the UN Charter. Although the majority of multinational peace operations take place under the command and control of either the UN or the North Atlantic Treaty Organisation (NATO), this article also bears in mind the growing role played by other international organisations such as the African Union (AU) or the European Union (EU). The expression ‘peace forces’ and ‘multinational forces’ will be used interchangeably in this document.

2 Shraga, Daphna and Zacklin, Ralph, ‘The Applicability of International Humanitarian Law to United Nations Peacekeeping Operations: Conceptual, Legal and Practical Issues’, Report to the Symposium on Humanitarian Action and Peacekeeping Operations, 22–24 June 1994, ICRC, Geneva, 2004, pp. 39–48Google Scholar; Daphna Shraga, ‘The Applicability of International Humanitarian Law to Peace Operations, from Rejection to Acceptance’, paper submitted to the 31^st Round Table on Current Problems of International Humanitarian Law, International Humanitarian Law, Human Rights and Peace Operations, 4–6 September 2008, International Institute of Humanitarian Law, San Remo, 2009, pp. 82–89.

3 See, for example, the position expressed in 2008 by French Minister of Foreign Affairs Bernard Kouchner before a parliamentary commission. In his opinion, France was not engaged in armed conflict in Afghanistan, because its troops were operating under a UN Security Council resolution with a view to restoring international peace and security in accordance with the UN Charter. See Assemblée Nationale, XIII^e Législature, Compte rendu n°46, Commission de la Défense Nationale et des Forces Armées, mardi 28 août 2008, p. 16.

4 Engdahl, Ola, ‘Multinational Peace Operations Forces Involved in Armed Conflict: Who are the Parties?’, in Mujezinović, KjetilCamilla, LarsenCooper, Gundahl and Nystuen, Gro (eds), Searching for a ‘Principle of Humanity’ in International Humanitarian Law, Cambridge, 2012, p. 259Google Scholar. The author refers to a statement by the Norwegian prime minister to the effect that Norwegian soldiers could not be considered legitimate targets while participating in NATO operations in Libya, because they were on a UN mission.

5 On 4 April 2011, Reuters quoted UN Secretary-General Ban Ki-moon as saying ‘let me emphasise that the ONUCI is not party to the conflict. In line with its Security Council mandate, the mission has taken this action in self-defence and to protect civilians’. A military court in Canada also adopted this position in 1996: see Court Martial Appeal Court of Canada, Her Majesty the Queen v. Private DJ Brocklebank, Court File No. CMAC-383, 2 April 1996, 106, Canadian Criminal Cases, 134 DLR (4^th) 377. In this case, the Court did not consider a UN peacekeeping mission to be a party to an armed conflict. However, the Court used a very abstract, old-fashioned interpretation of the term ‘peacekeeping mission’ in order to find that Chapter VI missions can never become a party to an armed conflict. The Court disregarded the fact that the blurring of the distinction between peacekeeping and peace enforcement in contemporary missions means that in some circumstances forces deployed under a Chapter VI mandate can perfectly well be drawn into hostilities.

6 Paul Berman, ‘When Does Violence Cross the Armed Conflict Threshold? Current Dilemmas’, Proceedings of the 13th Bruges Colloquium, Scope of Application of International Humanitarian Law, 18–19 October 2012, Collegium No. 43, Autumn 2013, College of Europe–ICRC, p. 41.

7 The argument that multinational forces may not be deemed a party to an armed conflict (and are therefore not bound by this body of law) does not rest on any firm basis. Indeed, an analysis of various military manuals shows that some of them expressly qualify peace forces as a party to an armed conflict (United States, FM 27-10, Department of the Army Field Manual, The Law of Land Warfare, July 1956, Appendix A-3s, section 8. A; Nigeria, Directorate of Legal Services of the Nigerian Army, International Humanitarian Law (IHL), pp. 26–27; Peru, Ministry of Defence, Manual para las Fuerzas Armadas, May 2010, p. 242; Spain, General Staff of the Armed Forces, Orientaciones. El Derecho de los Conflictos Armados, March 1996, Vol. I, sections 1–7 and 1–8) while others, without specifically referring to multinational forces as a party to an armed conflict, nonetheless recognise that IHL might be applicable to their military operations under certain circumstances (see, for example, Argentina, Ministry of Defence, Manual de Derecho Internacional de los Conflictos Armados, 2010, pp. 79–85; Australia, Royal Australian Air Force, Operations Law for RAAF Commanders, 2^nd edition, 2004, p. 37; Germany, Federal Ministry of Defence, Humanitarian Law in Armed Conflicts – Manual, August 1992, p. 24; New Zealand, New Zealand Defence Force, Interim Law of Armed Conflict Manual, 1992, pp. 19–3, para. 1902.2; The Netherlands, Humanitair Oorlogsrecht, Handleiding, 2005, p. 207). In this respect, the UK Joint Service Manual of the Law of Armed Conflict is probably one of the most significant: ‘14. 3. The extent to which PSO (peace support operations) forces are subject to the law of armed conflict depends upon whether they are party to an armed conflict with the armed forces of a state or an entity which, for these purposes, is treated as a state. …

14.5. A PSO force can become party to an armed conflict, and thus subject to the law of armed conflict:

a. where it was mandated from the outset to engage in hostilities with opposing armed forces as part of its mission …; b. where its personnel, though not originally charged with such a task, become involved in hostilities as combatants … to such a degree that an armed conflict comes into being between the PSO force and the opposing forces. The latter situation may arise in any type of PSO. …

14.7 It is not always easy to determine whether a PSO force has become a party to an armed conflict or to fix the precise moment at which that event has occurred …’. British Ministry of Defence, The Joint Service Manual of the Law of Armed Conflict, 2004, pp. 378–379.

A similar position was already expressed by the EU in 2002 on the occasion of the Salamanca Presidency Declaration according to which ‘respect [for IHL] is relevant in EU-led operations when the situation they are operating in constitutes an armed conflict to which the forces are party’: see The Outcome of the International Humanitarian Law Seminar of 22–24 April 2002 in Salamanca, doc. DIH/Rev.01.Corr1. In this issue of the Review, Frederik Naert expresses the opinion that ‘in the case of a military mission in a theatre where an armed conflict is ongoing, a robust mandate may lead to the EU forces becoming engaged in combat and becoming a party to the conflict, even if this is not intended.’ In her contribution, Katarina Grenfell states that: ‘In accordance with general principles of IHL, the writer understands that the principles and rules of IHL as set out in the Secretary-General's Bulletin apply in respect of a UN peacekeeping operation whenever it engages in such level of hostilities with a state or sufficiently organised non-state armed group as would render it a “party to a conflict”.’ Lastly, it must be noted that the Institute of International Law adopted resolutions in 1971, 1975 and 1999 expressly recognising that UN forces can be engaged in armed conflict.

8 The nature of the mandate assigned by the Security Council has a bearing only on the possibility that multinational forces might have to resort to force and thus become party to an armed conflict. For a contrary opinion, see Bloom, E. T., ‘Protecting Peacekeepers: the Convention on the Safety of United Nations and Associated Personnel’, in American Journal of International Law, Vol. 89, 1995, p. 626CrossRefGoogle Scholar.

9 One example was the deployment of EU forces in the DRC in 2003. Although acting under Resolution 1484 adopted under Chapter VII, the European troops were not drawn into hostilities and never had to apply IHL while in action; Frederik Naert, ‘The Application of International Humanitarian Law and Human Rights Law in CSDP Operations’, in Cannizzaro, Enzo, Palchetti, Paolo and Wessel, Ramses A. (eds), International Law as Law of the European Union, Martinus Nijhoff Publishers, Leiden, 2011, pp. 189–212Google Scholar. , especially p. 193

10 Giladi, Rotem, ‘The Jus Ad Bellum/Jus In Bello Distinction and the Law of Occupation’, in Israel Law Review, Vol. 41, 2008, p. 251CrossRefGoogle Scholar.

11 In this regard, the Commentary to Common Article 1 of the Geneva Conventions of 1949 explains that ‘the words “in all circumstances” mean that as soon as one of the conditions of application for which Article 2 provides is present, no Contracting Party can offer any valid pretext, legal or otherwise, for not respecting the Convention in its entirety. The words in question also mean that the application of the Convention does not depend on the character of the conflict. Whether a war is “just” or “unjust”, whether it is a war of aggression or of resistance to aggression, whether the intention is merely to occupy territory or to annex it, in no way affects the treatment protected persons should receive’: Pictet, Jean (ed.), Commentary to the Fourth Geneva Convention Relative to the Protection of Civilian Persons in Time of War, International Committee of the Red Cross, Geneva, 1958, pp. 16–17Google Scholar.

12 Since Article 31 of the 1969 Vienna Convention on the Law of Treaties indicates that the preamble to a legal instrument forms an integral part of the context in which the rules of that treaty must be interpreted, it is clear that any discussion of IHL applicability certainly cannot ignore the terms of the preamble to the Additional Protocol. These terms form the basis of an objective evaluation of the applicability of IHL, which is impervious to any political considerations and unaffected by the criteria of jus ad bellum.

13 US Military Tribunal at Nuremberg, Trial of Wilhelm List and others (The Hostages Trial), 1949, Law Reports of Trials of War Criminals Vol. VIII, United Nations War Crimes Commission, London, 1949, p. 59.

14 See Okimoto, Keiichiro, The Distinction and Relationship between Jus ad Bellum and Jus in Bello, Hart Publishing, 2011, p. 17Google Scholar; Orakhelashvili, Alexander, ‘Overlap and Convergence: the Interaction Between Jus ad Bellum and Jus in Bello’, in Journal of Conflict and Security Law, Vol. 12, 2007, pp. 167–170Google Scholar.

15 See, for example, Rousseau, Charles, Le droit des conflits armés, Pédone, Paris, 1983, pp. 24–26Google Scholar; McDougal, Myres and Feliciano, Florentino, The International Law of War, New Haven Press, 1994, pp. 530–542Google Scholar; Dinstein, Yoram, War, Aggression and Self-Defence, 4^th ed., Cambridge University Press, 2004, pp. 156–163Google Scholar; Green, Leslie, The Contemporary Law of Armed Conflict, 2^nd ed., Manchester University Press, 2000, pp. 18–19Google Scholar; Greenwood, Christopher, ‘International Humanitarian Law’, in Kalshoven, Frits (ed.), The Centennial of the First International Peace Conference – Reports and Conclusions, Kluwer, Boston, 2000, pp. 173–192Google Scholar; Bugnion, François, ‘Guerre juste, guerre d'agression, et droit international humanitaire’, in International Review of the Red Cross, Vol. 84, No. 847, September 2002, pp. 523–546Google Scholar; K. Okimoto, above note 14; Sassòli, Marco, ‘Ius ad Bellum and Ius in Bello, the Separation between the Legality of the Use of Force and Humanitarian Rules to be Respected in Warfare: Crucial or Outdated?’, in International Law and Armed Conflict: Exploring the Fault Lines, Essays in Honour of Yoram Dinstein, Martinus Nijhoff Publishers, 2007, pp. 241–264Google Scholar; Greenwood, Christopher, ‘The Relationship between Jus ad Bellum and Jus in Bello’, in Review of International Studies, Vol. 9, 1983, pp. 221–234Google Scholar; Goodman, Ryan, ‘Controlling the Recourse to War by Modifying Jus in Bello’, in Yearbook of International Humanitarian Law, Vol. 12, 2009, pp. 53–84Google Scholar; Moussa, Jasmine, ‘Can “Jus ad Bellum” Override “Jus in Bello”? Reaffirming the Separation of the Two Bodies of Law’, in International Review of the Red Cross, Vol. 90, No. 872, December 2008, pp. 963–990Google Scholar. These writers generally endorse what was so aptly said by Hersch Lauterpacht in 1940 when he wrote in Oppenheim's International Law, 6^th ed., 1940, pp. 174–175, that ‘whatever may be the cause of a war that has broken out, and whether or not the cause may be a so-called just cause, the same rules of international law are valid as to what must not be done, and what must be done by the belligerents themselves in making war with each other …. This is so even if the declaration of war is ipso facto a violation of international law, as when a belligerent declares war upon a neutral State for refusing passage to its troops or when a State goes to war in patent violation of its obligation under the Covenant of the League or of the General Treaty for the Renunciation of War … . The rules of international law apply to war from whatever cause it originates.’ This legal construct is unimpeachably modern; it can be transposed to peace operations in order to affirm forcefully that IHL applies whenever multinational forces are involved in either an international or a non-international armed conflict.

16 See, for example, The Interim Law of Armed Conflict Manual, DM 112, Directorate of Legal Services, New Zealand Defence Force, Wellington, New Zealand, 1992, p. 19, para. 1902; The Joint Service Manual…, above note 7, section 3.12 entitled ‘Universal Application of the Law of Armed Conflict’.

17 See K. Grenfell's contribution in this issue of the Review.

18 Given that recent peace operations show that multinational forces are more likely to become embroiled in non-international than in international armed conflicts, the question is whether the strict separation between jus ad bellum and jus in bello may be invoked in such situations and whether the corollary principle of the equality between belligerents remains equally valid. Indeed, it might be argued that the strict separation is invalid in a non-international armed conflict as international law does not prohibit such conflicts and recognises that every state has the right to use force in order to preserve its territorial integrity and quell an insurgency. However, at the domestic level, almost all states have passed legislation prohibiting citizens from taking arms against the government. It is therefore essential to examine the relationship between this kind of domestic law and IHL. Does the fact that one of the parties to the non-international armed conflict has violated domestic law by resorting to force against the government preclude the application of IHL and its underlying principles? It is submitted here that the IHL applicable to a non-international armed conflict has to be the same for both parties, regardless of the fact that one belligerent is fighting in breach of internal law. See for example, Bugnion, François, ‘Jus ad Bellum, Jus in Bello and Non-International Armed Conflicts’, in Yearbook of International Humanitarian Law, Vol. 6, 2003, pp. 167–198CrossRefGoogle Scholar; Marco Sassòli, ‘Collective Security Operations and International Humanitarian Law’, in Proceedings of the Bruges Colloquium, Relevance of International Humanitarian Law to Non-State Actors, 25–26 October 2002, Collegium No. 27, Spring 2003, pp. 84–85. In other words, the unequal legal status of the belligerents under domestic law does not affect the fact that IHL applies equally to all parties involved in a non-international armed conflict, including multinational forces. Furthermore, in accordance with Article 27 of the 1969 Vienna Convention on the Law of Treaties which stipulates that ‘A party may not invoke the provisions of its internal law as justification for its failure to perform a treaty’, the domestic law of the state in the territory of which the peace operation takes place and the internal law of the TCCs cannot be used as grounds for disregarding the IHL applicable to a non-international armed conflict. In this regard, the wording of the first paragraph of Common Article 3 of the Geneva Conventions may be interpreted as ruling out any subordination of jus in bello to jus ad bellum in a non-international armed conflict.

19 Gary Sharp, Walter, ‘Protecting the Avatars of International Peace and Security’, in Duke Journal of International and Comparative Law, Vol. 7, 1996, pp. 93–183Google Scholar. From the same author, see also ‘Revoking an Aggressor's License to Kill Military Forces Serving the United Nations: Making Deterrence Personal’, in Maryland Journal of International Law, Vol. 22, 1998, pp. 3–78.

20 Questions for the Record Submitted to Legal Adviser Harold Hongju Koh by Senator Richard G. Lugar, Hearing before the Committee on Foreign Relations, US Senate, June 28, 2011, p. 54, available at www.fas.org/irp/congress/2011_hr/libya.pdf (all internet references were accessed in March 2014).

21 Interim Law of Armed Conflict Manual, DM 112, Directorate of Legal Services, New Zealand Defence Force, Wellington, New Zealand, 1992, p. 19, para. 1902: ‘Military operations by or on behalf of the United Nations will only be taken against a State regarded as an aggressor, or otherwise in breach of its obligations under international law. To the extent that the law of armed conflict applies to such operations, it does so on the basis of complete equality. That is to say, the fact that one side is acting as a law enforcer against another party which is a law breaker does not invalidate the operation of [IHL].’

22 Roberts, Adam, ‘The Equal Application of the Laws of War: a Principle Under Pressure’, in International Review of the Red Cross, Vol. 90, No. 872, December 2008, pp. 952–956CrossRefGoogle Scholar. It is also worth noting that, in 1963, the Institute of International Law explored the question of whether the principle of equality between belligerents would apply in the event of UN forces becoming implicated in an armed conflict (see Annuaire Français de Droit International, Vol. 9, 1963, pp. 1248–1949). This subject was again examined by the Institute in 1971. In a resolution adopted that year, it concluded that all the humanitarian rules of the law of armed conflict should be observed by UN forces (Institute of International Law, Zagreb Session, 3 September 1971, resolution on ‘Conditions of Application of Humanitarian Rules of Armed Conflict to Hostilities in which United Nations Forces may be Engaged’, in particular Art. 2). In 1975, the Institute decided that, in general, other ‘non-humanitarian’ rules of armed conflict should be respected in hostilities in which UN forces were engaged and it reaffirmed that UN forces should not be exempted from the application of the principle of equality between belligerents (Institute of International Law, Wiesbaden Session, 13 August 1975, resolution on ‘Conditions of Application of Rules, other than Humanitarian Rules, of Armed Conflict to Hostilities in which United Nations Forces may be Engaged’).

23 ICRC, Customary International Humanitarian Law, Vol. I: Rules, Jean-Marie Henckaerts and Louise Doswald-Beck (eds), Cambridge University Press, Cambridge, 2005, Rule 33 and its commentaries, Vol. I, pp. 112–114.

24 A. Roberts, above note 22, p. 955.

25 Article 2(2) of the 1994 Safety Convention reads as follows: ‘This Convention shall not apply to a United Nations operation authorised by the Security Council as an enforcement action under Chapter VII of the Charter of the United Nations in which any of the personnel are engaged as combatants against organised armed forces and to which the law of international armed conflict applies'. This clause has been referred to as a ‘switch clause’ stipulating conditions where the Convention no longer applies. This provision is a result of a compromise between those favouring mutual exclusion (i.e., the Convention would not apply when IHL covers UN forces irrespective of the nature of the armed conflict in which they are engaged) and those willing to create an overlap between the Convention and IHL in the event of a non-international armed conflict. Consequently, Article 2(2) is open to various interpretations and has been criticised for having rendered the applicability of IHL and the 1994 Safety Convention unclear. See for instance Engdahl, Ola, Protection of Personnel in Peace Operations: the Role of the ‘Safety Convention’ against the Background of General International Law, Martinus Nijhoff Publishers, 2007, pp. 233–241Google Scholar; Engdahl, Ola, ‘The Status of Peace Operation Personnel under International Humanitarian Law’, in Yearbook of International Humanitarian Law, Vol. 11, 2008, pp. 121–129Google Scholar.

26 O. Engdahl, Protection of Personnel in Peace Operations, above note 25; Arsanjani, Mahnoush H., ‘Defending the Blue Helmets: Protection of United Nations personnel’, in Condorelli, Luigi, La Rosa, Anne-Marie and Scherrer, Sylvie (eds), The United Nations and International Humanitarian Law, Actes du colloque international à l'occasion du cinquantième anniversaire de l'ONU, Pédone, Geneva, 1995, pp. 143–144Google Scholar. For a contrary view, see Okimoto, Keiichiro, ‘Violations of International Humanitarian Law by United Nations Forces and Their Legal Consequences’, in Yearbook of International Humanitarian Law, Vol. 8, 2003, p. 214Google Scholar; Glick, Richard D., ‘Lip Service to the Laws of War: Humanitarian Law and the United Nations Armed Forces’, in Michigan Journal of International Law, 1995, pp. 82–83Google Scholar; Vaios Koutroulis, ‘Problèmes de symétrie: des brèches du mur de Berlin aux brèches au principe de l’égalité des belligérants?’, paper presented at the 4^th Biennial Conference of the European Society of international Law in Cambridge, available at: www.esil-en.law.cam.ac.uk/Media/Draft_Papers/Agora/Koutroulis.pdf.

27 Ibid.

28 For the conditions under which non-UN peace forces would qualify as ‘associated personnel’ under the 1994 Safety Convention, see O. Engdahl, Protection of Personnel in Peace Operations, above note 25, pp. 218–224.

29 See Dieter Fleck's article in this edition of the Review.

30 Article 20 of the Convention reads as follows:

‘Nothing in this Convention shall affect:

(a) The applicability of international humanitarian law and universally recognised standards of human rights as contained in international instruments in relation to the protection of United Nations operations and United Nations and associated personnel or the responsibility of such personnel to respect such law and standards;

(b) The rights and obligations of States, consistent with the Charter of the United Nations, regarding the consent to entry of persons into their territories;

(c) The obligation of United Nations and associated personnel to act in accordance with the terms of the mandate of a United Nations operation;

(d) The right of States which voluntarily contribute personnel to a United Nations operation to withdraw their personnel from participation in such operation; or

(e) The entitlement to appropriate compensation payable in the event of death, disability, injury or illness attributable to peace-keeping service by persons voluntarily contributed by States to United Nations operations'.

31 Bouvier, Antoine, ‘Convention on the Safety of United Nations and Associated Personnel: Presentation and Analysis’, in International Review of the Red Cross, No. 309, pp. 638–666Google Scholar; Bourloyannis-Vrailas, M.-Christiane, ‘The Convention on the Safety of United Nations and Associated Personnel’, in International and Comparative Law Quarterly, Vol. 44, 1995, pp. 583–584Google Scholar.

32 Dörmann, Knut, Elements of War Crimes under the Rome Statute of the International Criminal Court, Cambridge University Press, 2003, pp. 452–457CrossRefGoogle Scholar. In 2000, the UN Secretary-General stressed that it should not be the nature or character of the conflict that determined whether the Convention or IHL applied but whether ‘in any type of conflict, members of the United Nations peacekeeping operations are actively engaged therein as combatants, or are otherwise entitled to the protection given to civilians under the international law of armed conflict’: Report of the Secretary-General on the Scope of Legal Protection under the Convention on the Safety of United Nations and Associated personnel, UN Doc. A/55/637 (2000), footnote 3, p. 9. Furthermore, the Secretary-General's Bulletin on the Observance by United Nations Forces of International Humanitarian Law, UN Doc. ST/SGB/1993/13, 6 August 1999 (hereinafter the Secretary-General's Bulletin or the Bulletin), confirms the position adopted by states in the Rome Statute, as the Bulletin specifies in section 1.2 that ‘the promulgation of this bulletin does not affect the protected status of members of peacekeeping operations under the 1994 Convention on the Safety of United Nations and Associated Personnel or their status as non-combatants, as long as they are entitled to the protection given to civilians under international law of armed conflict’ (emphasis added).

33 For instance David, Eric, Principes de droit des conflits armés, 5^th ed., Bruylant, Bruxelles, 2012, p. 120Google Scholar; Kolb, Robert and Hyde, Richard, An Introduction to the International Law of Armed Conflicts, Hart Publishing, Oxford, 2008, pp. 75–76Google Scholar; Fleck, Dieter (ed.) and Bothe, Michael, The Handbook of International Humanitarian Law, Oxford University Press, 2008, pp. 47–48Google Scholar; Corn, Geoffrey S. et al. , The Law of Armed Conflict: An Operational Approach, Wolters Kluwer Law & Business, New York, 2012, pp. 72Google Scholar and 80; Porretto, Gabriele and Vité, Sylvain, ‘The Application of International Humanitarian Law and Human Rights to International Organisations’, in Research Papers Series No. 1, Centre Universitaire de Droit International Humanitaire, 2006, p. 32Google Scholar; D. Shraga, ‘The Applicability of International Humanitarian Law to Peace Operations’, above note 2, p. 94; International Law Association, report on use of force, The Hague Conference, 2010, p. 33: ‘The de jure state or situation of armed conflict depends on the presence of actual and observable facts, in other words, objective criteria.’

34 See, for example, ICTR, The Prosecutor v. Rutaganda, Case No. ICTR-96–3-T, Judgment (Trial Chamber I), 6 December 1999, para. 92: ‘the definition of an armed conflict per se is termed in the abstract, and whether or not a situation can be described as an “armed conflict”, meeting the criteria of common Article 3, is to be decided upon on a case-by-case basis'; ICTY, The Prosecutor v. Limaj et al., Case No. IT-03–66-T, Judgment (Trial Chamber II), 30 November 2005, para. 90: ‘the determination of the intensity of a conflict and the organisation of the parties are factual matters which need to be decided in light of the particular evidence and on a case-by-case basis’; Inter-American Commission on Human Rights, Report No. 55/97, Case No. 11.137, Juan Carlos Abella v. Argentina, 18 November 1997, para. 153: ‘The line separating an especially violent situation of internal disturbances from the “lowest” level Article 3 armed conflict may sometimes be blurred and, thus, not easily determined. When faced with making such a determination, what is required in the final analysis is a good faith and objective analysis of the facts in each particular case.’ As far as the International Criminal Court is concerned, in Lubanga and Bemba, the Trial and Pre-Trial Chambers each looked at the test established by the ICTY in Tadić in order to determine the existence of an armed conflict and then applied this test to the facts in the case. The ICC therefore implicitly accepts that the existence of an armed conflict has to be determined on the basis of the facts at the time. See ICC, The Prosecutor v. Thomas Lubanga Dyilo, Trial Judgment (Trial Chamber), 14 March 2012, paras 533 ff.; ICC, The Prosecutor v. Jean-Pierre Bemba Gombo, Decision Pursuant to Art. 61(7)(a) and (b) of the Rome Statute on the Charges of the Prosecutor (Pre-Trial Chamber), 15 June 2009, paras 220 ff.

35 ICTY, The Prosecutor v. Boškovski, Case No. IT-04-82-T, Judgment (Trial Chamber II), 10 July 2008, para. 174. In para. 176, the Trial Chamber also indicated that ‘Trial Chambers have assessed the existence of armed conflict by reference to objective indicative factors of intensity of the fighting and the organisation of the armed group or groups involved depending on the facts of each case.’

36 ICTY, The Prosecutor v. Milutinovic, Case No. IT-05-87-T, Judgment (Trial Chamber), 26 February 2009, para. 125. See also ICTR, The Prosecutor v. Akayesu (ICTR-96-4-T), Judgment (Trial Chamber I), 2 September 1998, para. 603: ‘If the application of international humanitarian law depended solely on the discretionary judgment of the parties to the conflict, in most cases there would be a tendency for the conflict to be minimised by the parties thereto.’

37 Executive Series, Australian Defence Doctrine Publication 06.4, 11 May 2006, chapter 3.5. Along the same lines, the United Kingdom's Joint Service Manual, above note 7, provides in its section 3.3.1 that ‘whether any particular intervention crosses the threshold of armed conflict will depend on all the surrounding circumstances’.

38 British Ministry of Defence, The Joint Service Manual…, above note 7, section 14.7, p. 379.

39 In 2004, an ICRC report summing up the discussions that took place on the occasion of an expert meeting on IHL and multinational peace operations underlined the fact that the participants ‘could not reach an agreement on the threshold that triggers applicability of IHL [to multinational forces]’; Alexandre Faite and Jérémie Labbé Grenier, Report to the Expert meeting on Multinational Peace Operations, Applicability of International Humanitarian Law and International Human Rights Law to UN Mandated Forces, ICRC, Geneva, 2004, p. 10. Christopher Greenwood has underlined the fact that the use of force by peace operations is sometimes judged on a different scale allowing a higher level of force than is the case for other armed forces before IHL applies: see Christopher Greenwood, ‘International Humanitarian Law and United Nations Military Operations’, in Yearbook of International Humanitarian Law, Vol. 1, 1998, p. 24.

40 ICRC Opinion Paper, ‘How is the Term “Armed Conflict” Defined in International Humanitarian Law?’, March 2008, available at: www.icrc.org/eng/assets/files/other/opinion-paper-armed-conflict.pdf; ‘International Humanitarian Law and the Challenges of Contemporary Armed Conflicts’, Report of the 31^st International Conference of the Red Cross and Red Crescent, Geneva, Switzerland, 28 November–1 December 2011, pp. 7–13, available at: www.icrc.org/eng/assets/files/red-cross-crescent-movement/31st-international-conference/31-int-conference-ihl-challenges-report-11-5-1-2-en.pdf.

41 See for example Fleck, Dieter, The Handbook of Humanitarian Law in Armed Conflicts, Oxford University Press, Oxford, 2004, pp. 39–49Google Scholar; Sassòli, Marco, Antoine Bouvier and Anne Quintin, How Does Law Protect in War?, ICRC, Geneva, 3^rd ed., 2011, pp. 21–22Google Scholar; Solis, Gary, The Law of Armed Conflict: International Humanitarian Law in War, Cambridge University Press, Cambridge, 2010, pp. 149–156Google Scholar; Wilmshurst, Elizabeth (ed.), International Law and the Classification of Conflicts, Oxford University Press, Oxford, 2012Google Scholar; Daniel Bethlehem, Sandesh Sivakumaran, Noam Lubell and Philip Leach, Conflict Classification: the Way Forward, International Law Meeting Summary, Chatham House, London, 2012, available at: www.chathamhouse.org/sites/default/files/public/Research/International%20Law/011012summary.pdf; Vité, Sylvain, ‘Typology of Armed Conflicts in International Humanitarian Law: Legal Concepts and Actual Situations’, in International Review of the Red Cross, Vol. 91, No. 873, March 2009, pp. 69–94Google Scholar.

42 British Ministry of Defence, The Joint Service Manual…, above note 7, section 14.6, p. 379.

43 Ferraro, Tristan, ‘The Issue of International Humanitarian Law Applicability to Recent UN, NATO and African Union Peace Operations (Libya, Somalia, Democratic Republic of Congo, Ivory Coast…)’, in Horvat, Stanislas and Benatar, Marco (eds), Legal Interoperability and Ensuring Observance of the Law Applicable in Multinational Deployments, Proceedings of the 19^th International Congress (Québec City, 1–5 May 2012)Google Scholar, International Society for Military Law and the Law of War, Brussels, 2013, pp. 315–323.

44 It may be argued that a customary rule has crystallised, making it possible to extend the scope rationae personae of international armed conflicts to international organisations: see Dapo Akande, ‘Classification of Armed Conflicts: Relevant Legal Concepts’, in E. Wilmshurst (ed.), above note 41, pp. 32–79.

45 It must be made clear that the notion of belligerent intent, which is crucial for determining whether an international armed conflict exists, must not be confused with the notion of animus belligerendi which is intrinsic to the legal concept of war. While animus belligerendi is regarded as a prerequisite for the existence of a state of war, as an indicium of the subjective dimension of a declared war, the reference to the notion of belligerent intent has only evidentiary value and can in no way be interpreted as challenging the objective dimension inherent to the concept of international armed conflict.

46 ICTY, The Prosecutor v. Boškoski, Case No. IT-04-82-T, Judgment (Trial Chamber), 10 July 2008, paras. 177–193.

47 See, in particular, ICTY, The Prosecutor v. Tadić, Case No. IT-94-1-T, Judgment (Trial Chamber), 7 May 1997, paras. 561–568; ICTY, The Prosecutor v. Limaj et al., Case No. IT-03-66-T, Judgment (Trial Chamber), 30 November 2005, paras. 94–170; ICTY, The Prosecutor v. Haradinaj et al., Case No. IT-04-84-T, Judgment (Trial Chamber), 3 April 2008, paras. 50–60; ICTY, The Prosecutor v. Boškoski, Case No. IT-04-82-T, Judgment (Trial Chamber), 10 July 2008, paras. 194–206.

48 A more restrictive definition of non-international armed conflicts was adopted in Additional Protocol II to the Geneva Conventions. Article 1(1) of this instrument specifies that it applies to armed conflicts ‘which take place in the territory of a High Contracting Party between its armed forces and dissident armed forces or other organised armed groups which, under responsible command, exercise such control over a part of its territory as to enable them to carry out sustained and concerted military operations and to implement this Protocol.’ This definition of non-international armed conflicts is narrower than the one derived from Common Article 3 of the Geneva Conventions. Indeed, it introduces a territorial requirement by providing that the non-state actor opposing government forces must exert such territorial control ‘as to enable [it] to carry out sustained and concerted military operations and to implement this Protocol.’ In addition, contrary to Common Article 3, the Protocol excludes armed confrontation between non-state armed groups from its field of application. It is submitted here that since the definition of non-international armed conflicts set forth in this Protocol is narrower, it is relevant to the application of the Protocol alone, but not to the law of non-international armed conflicts in general. Indeed, as Article 1(1) of this instrument plainly states, it ‘develops and supplements’ Common Article 3 ‘without modifying its existing conditions of application’.

49 The ICRC was involved at the drafting stage, but it had no say on the final version of the Bulletin which is, strictly speaking, a UN document. ICRC participation in the drafting process does not mean that this document has been endorsed by the ICRC. As it stands, some elements of the Bulletin, in particular its field of application, call for clarification and do not necessarily reflect IHL provisions, in particular those laying down the conditions for determining IHL applicability to a de facto situation. See Anne Ryniker, ‘Respect du droit international humanitaire par les forces des Nations Unies, quelques commentaires à propos de la Circulaire du Secrétaire Général des Nations Unies du 6 août 1999’, in International Review of the Red Cross, Vol. 81, No. 836, December 1999, pp. 795–805; Marten Zwanenburg, ‘The Secretary General's Bulletin on Observance by UN Forces of IHL: a Pyrrhic Victory?’, in Revue Militaire et de Droit de la Guerre, 2000, p. 17.

50 On the contrary, the phrase referring to self-defence contained in section 1.1 of the Bulletin should be construed so that the use of force by UN forces in self-defence may trigger IHL application only once such use of force meets the conditions for IHL applicability.

51 ‘Answers to the Questionnaire, Part II: Applicability of IHL in Peacekeeping Operations’, in Report Presented to the 18^th Congress on Practice and Customary Law in Military Operations including Peace Support Operations, International Society for Military Law and the Law of War, La Marsa, 5–9 May 2009, p. 26, available at: www.ismllw.org/congres/General%20Report%20Congress.pdf.

52 O. Engdahl, ‘The Status of Peace Operation Personnel…’, above note 25, p. 117: ‘Even if military force is utilised for the purposes of self-defence, such force must also be judged against the objective criterion of the level of force applied (intensity of the conflict) and the level of organisation of the opposing forces. The argument of self-defence cannot be relied upon indefinitely in order to escape the application of IHL.’

53 ICTY, The Prosecutor v. Tadić, Decision on the Defence Motion for Interlocutory Appeal on Jurisdiction (Appeals Chamber), 2 October 1995, para. 69.

54 See Cullen, Anthony, The Concept of Non-International Armed Conflict in International Humanitarian Law, Cambridge University Press, Cambridge, 2010, pp. 205Google Scholar ff.; Zimmermann, Andreas, ‘War Crimes Committed in an Armed Conflict not of an International Character’, in Triffterer, Otto (ed.), Commentary on the Statute of the International Criminal Court, Verlagsgesellschaft, Baden-Baden, 1999, p. 285Google Scholar; Boelaert-Suominen, Sonja, ‘Commentary: the Yugoslav Tribunal and the Common Core of Humanitarian Law Applicable to All Conflicts’, in Leiden Journal of International Law, 2000, p. 634Google Scholar; Thahzib-lie, Bahia and Swaak-Goldman, Olivia, ‘Determining the Threshold for the Application of International Humanitarian Law’, in Lijnzaad, Liesbeth, Van Sambeek, Johanna and Thahzib-lie, Bahia (eds), Making the Voice of Humanity Heard, Martinus Nijhoff Publishers, Leiden/Boston, 2004, p. 248Google Scholar.

55 Robert Kolb for instance argues that the use of force by multinational peace forces in self-defence against sporadic attacks would not turn these troops into parties to the pre-existing armed conflict. However, he adds that ‘if the attacks degenerate into a general pattern and the forces start conducting military operations on their own so as to respond to the acts of war of the other side, we would find ourselves in the context of an armed conflict’: Robert Kolb, ‘Background Document 1: Applicability of International Humanitarian Law to Forces under the Command of an International Organisation’, in A. Faite and J. Labbé Grenier, above note 39, p. 68. However, this position was not shared by the Trial Chamber of the Special Court for Sierra Leone, which stated that ‘as with all civilians [the peacekeepers’] protection would not cease if the personnel use armed force only in exercising their right to individual self-defence. Likewise, the Chamber opines that the use of force by peacekeepers in self-defence in the discharge of their mandate, provided that it is limited to such use, would not alter or diminish the protection afforded to peacekeepers': Special Court for Sierra Leone, The Prosecutor v. Sesay, Kallon and Gbao (RUF case), Judgment (Trial Chamber), 2 March 2009, SCSL-04-15-T, para. 233. An identical position was taken by the ICC Pre-Trial Chamber, on 8 February 2010, in The Prosecutor v. Bahar Idriss Abu Garda, Case No. ICC-02/05-02/09, Decision on the Confirmation of Charges, ICC-02/05-02/09, para. 83. However, the Court could be challenged when it argues that multinational forces acting in self-defence can never be deemed to be involved in armed conflict. Such a position means in practice that multinational forces could be considered party to an armed conflict only when they initiate the fighting. If one takes the position of the Special Court for Sierra Leone a step further, no military action undertaken by non-state organised armed groups against multinational forces could ever reach the threshold of armed conflict within the meaning of IHL if the multinational forces' response cannot be used in the classification process. Furthermore the risk would also be that attacks against the latter, when they are connected with the armed conflict, would be qualified as a war crime, which is at odds with the IHL principle of equality between belligerents. The position taken by the Trial Chamber is not therefore consistent with IHL, as it disregards the possibility under IHL that the use of force in self-defence by multinational forces might well trigger the application of IHL and turn these forces into a party to a non-international armed conflict. In this regard, it is worth noting that the UK military manual on the law of armed conflict acknowledges this possibility and stresses that ‘a PSO force can become party to an armed conflict and thus subject to the law of armed conflict … where its personnel, though not originally charged with such a task, become involved in hostilities as combatants (whether as the result of their own initiative or because they are attacked by other forces) to such a degree that an armed conflict comes into being between the PSO force and the opposing forces. The latter situation may arise in any type of PSO.’ British Ministry of Defence, The Joint Service Manual…, above note 7, section 14.5, pp. 378–379.

56 Ibid., pp. 24 and 34.

57 See above.

58 As discussed above, Article 2(2) of the 1994 Safety Convention indicates that the latter does not apply when UN forces are involved in an international armed conflict.

59 See Final Report on the Meaning of Armed Conflict in International Law, International Law Association, Committee on the Use of Force, The Hague, 2010, p. 17: ‘If a low threshold of hostilities is adopted for the application of the [1994 Safety] Convention, this will have the effect of rendering virtually non-existent the protections offered by the Convention.’

60 Cour Militaire, Ministère Public et Centre pour l’égalité des chances et la lutte contre le racisme v. C… and B…, 17 December 1997, Journal des Tribunaux, 4 April 1998, pp. 288–289: ‘Attendu qu'avant tout, il faut relever qu'il n'y a pas eu de situation de conflit et, a fortiori, pas de situation de conflit armé, qui soit survenue entre la République démocratique de Somalie et les Nations Unies ; Que, comme il a été dit plus haut, les troupes des Nations Unies ne sont pas entrées en jeu dans le cadre des articles 43 et suivants de la Charte, mais bien comme une force de paix dotée de compétences coercitives pour l'exécution de missions bien définies ;… Que la cour n'a pas connaissance d'autres données, d'où il résulterait que les forces de l'ONU se seraient livrées de facto, sur le territoire de la Somalie – en contravention à leur mission légale – à des opérations de combat (1) permanentes, (2) généralisées et (3) structurées contre une ou plusieurs bandes armées rivales ; Que c'est seulement dans cette hypothèse que la force de paix serait devenue une partie au conflit…’

61 Shraga, Daphna, ‘The Secretary General's Bulletin on the Observance by UN Forces of International Humanitarian Law: a Decade Later’, in Israel Yearbook on Human Rights, Vol. 39, 2009, p. 359Google Scholar; D. Shraga, ‘The Applicability of International Humanitarian Law to Peace Operations…’, above note 2, pp. 94–95.

62 In her article Daphna Shraga illustrates the ‘double key’ test with examples of military operations triggering the applicability of IHL to UN forces. These examples seem to demonstrate that a substantial threshold of intensity needs to be met in order to meet the second condition of the ‘double key’ test. They thus reflect the tendency to apply a higher threshold of intensity for determining the existence of an armed conflict – international or not – when multinational peace forces are involved and whether they should be considered parties to it within the meaning of IHL.

63 M. Zwanenburg, above note 49, p. 21: ‘The Bulletin follows the view that armed violence has to reach a certain level of intensity before IHL applies [to UN forces].’

64 One should note that, in this issue of the Review, when Katarina Grenfell, legal adviser at the UN Office of Legal Affairs, discusses the conditions under which IHL applies to UN forces, she does not refer to the above-mentioned ‘double key test’.

65 Cartledge, Garth J., ‘Legal Restraints on Military Personnel Deployed on Peacekeeping Operations’, in Durham, Helen and McCormarck, Timothy L. H. (eds), The Changing Face of Conflict and the Efficacy of International Humanitarian Law, Martinus Nijhoff Publishers, The Hague, 1999, pp. 125–130Google Scholar. See also O. Engdahl, ‘The Status of Peace Operation Personnel…’, above note 25, p. 118: ‘There would not seem to be support in law for a special threshold for applying IHL to peace operations forces. The point of departure must be that the same criteria for determining when such forces become involved in armed conflict apply as for other armed forces.’

66 ‘Answers to the Questionnaire…’, above note 51.

67 D. Shraga and R. Zacklin, above note 2, p. 48.

68 Ibid.

69 SC Res. 1906, 23 December 2009, paras. 21–23; SC Res. 1925, 28 May 2010, para. 12(h); SC Res. 2098, 28 March 2013, para. 12(b).

70 SC Res. 1386, 20 December 2001, para.1; SC Res.1510, 13 October 2003, para.1.

71 This position is without prejudice to jus ad bellum issues that might considerably limit the geographical spread of the conflict. Consent of the territorial state particularly matters in such circumstances. For further details on the geographical scope of application of IHL, see below.

72 When these weapons/ammunition are not immediately used by the supported party against its adversary, the causal relationship between their delivery and the harm inflicted by the supported party while using them is too indirect for such support to be deemed an integral part of the collective conduct of hostilities.

73 The term ‘hostilities’ cannot be restricted to actual fighting, to the neutralisation of a given object or the killing/capture of a certain person. It also encompasses certain logistical, intelligence or preparatory activities and, taken together, the belligerent's activities aimed at inflicting damage on the enemy. ‘Hostilities’ for the purposes of IHL would thus constitute the sum of hostile actions or all acts harmful to the adversary. The conduct in question has to be directed at the enemy or, at least, has to be closely related to action against the enemy. The concept of hostilities within the meaning of IHL is therefore broader than the mere use of force and includes all violent and non-violent measures which constitute an integral part of the same military operation aimed at destroying the enemy's military capacity or at hampering its military operations. In other words, the term ‘hostilities’ can be equated with the traditional term ‘acts of war’ which by their nature or purpose, and sometimes in conjunction with other action, are likely to cause harm to the personnel or equipment of the enemy armed forces. Melzer, Nils, Targeted Killing in International Law, Oxford University Press, Oxford, 2008, pp. 325–334CrossRefGoogle Scholar.

74 It is, however, questionable whether one should err on the side of caution when applying the support-based approach, because of its legal and practical implications for the legal status of the multinational forces. A cautious attitude would entail waiting until multiple acts had taken place before it might be said that this second condition had been fulfilled.

75 This would be the case, for instance, when the multinational forces’ action is so tenuously associated with the action of a party to the pre-existing conflict that it raises some doubts as to whether the action concerned can really be regarded as part of the collective conduct of hostilities.

76 In this regard, ultra vires action might well trigger the international responsibility of the TCC or international organisation in question, but would not be sufficient per se to turn it into a party to the pre-existing non-international armed conflict owing to a lack of any belligerent intent on the part of the entity to which the impugned act can be attributed.

77 In addressing this question, it is assumed that the international organisations involved in peace operations have the legal capacity to be bound by IHL. This capacity depends on the existence of the international organisations’ international legal personality. This article will proceed on the assumption that that the material capacity of an international organisation to be engaged in military operations entails its subjective capacity to be bound by IHL. In other words, if the constitutive document of an international organisation explicitly or implicitly provides for the possibility of deploying armed forces in a foreign country and allows it to contribute to the maintenance of international peace and security through military action, IHL may potentially be a legal frame of reference once these forces are involved in military operations reaching the level of an armed conflict. Hence an international organisation could perfectly well become a belligerent and be considered per se a party to an armed conflict, be it international or non-international in nature. As international organisations per se cannot be formally a party to any IHL treaties, only IHL customary rules will apply to international organisations engaged in armed conflicts. See Kolb, Robert, Porretto, Gabriele and Vité, Sylvain, L'application du droit international humanitaire et des droits de l'homme aux organisations internationales, forces de paix et administrations civiles transitoires, Bruylant, Bruxelles, 2005, pp. 121–128Google Scholar; Tristan Ferraro, ‘IHL Applicability to International Organisations Involved in Peace Operations’, Proceedings of the 12^th Bruges Colloquium, International Organisations’ Involvement in Peace Operations: Applicable Legal framework and the Issue of Responsibility, 20–21 October 2011, Collegium No. 42, Autumn 2012, College of Europe–ICRC, pp. 15–22.

78 Marten Zwanenburg, ‘International Organisations vs. Troop Contributing Countries: Which Should Be Considered as the Party to an Armed Conflict during Peace Operations?’, Proceedings of the 12^th Bruges Colloquium, International Organisations’ Involvement in Peace Operations: Applicable Legal Framework and the Issue of Responsibility, 20–21 October 2011, Collegium No. 42, Autumn 2012, College of Europe–ICRC, pp. 23–28; O. Engdahl, above note 4, pp. 233–271.

79 C2 refers to the authority vested in certain individuals or bodies to direct the action of and exercise authority over the armed forces. Most states and international organisations such as the UN and NATO have developed sophisticated, complex C2 structures and doctrines in order to achieve specific objectives and ensure that the armed forces put at their disposal operate within designated legal and policy guidelines. See Gill, Terry, ‘Legal Aspects of the Transfer of Authority in UN Peace Operations’, in Netherlands Yearbook of International Law, Vol. 42, December 2011, p. 45Google Scholar. In other words, the C2 structure provides the framework within which military resources drawn from states and international organisations can operate together effectively to accomplish a common mission generally assigned by the UN Security Council.

80 For a more detailed analysis of these issues, see Cathcart, Blaise, ‘Command and Control in Military Operations’, in Gill, Terry and Fleck, Dieter (eds), The Handbook of International Law of Military Operations, Oxford, 2010, pp. 235–244Google Scholar; T. Gill, above note 79, pp. 37–68.

81 ‘Full command’ is defined by NATO as ‘the military authority and responsibility of a commander to issue orders to subordinates. It covers every aspect of military operations and administration and exists only within national services.’ The term ‘command’ as used internationally implies a lesser degree of authority than when it is used in a purely national sense. No NATO or coalition commander has full command over the forces assigned to him since, when assigning forces to NATO, states will delegate only operational command or operational control. See NATO Standardisation Agency (NSA), NATO Glossary of Terms and Definitions (English and French) (hereinafter NATO Glossary), AAP-06, 2013, p. 2-F-7, available at: http://nsa.nato.int/nsa/zPublic/ap/aap6/AAP-6.pdf.

82 NATO has defined ‘operational command’ as ‘the authority granted to a commander to assign missions or tasks to subordinate commanders, to deploy units, to reassign forces, and to retain or delegate operational and/or tactical control as the commander deems necessary.’ NATO Glossary, above note 81, p. 2-O-3.

83 NATO has described ‘operational control’ as ‘the authority delegated to a commander to direct forces assigned so that the commander may accomplish specific missions or tasks which are usually limited by function, time, or location; to deploy units concerned, and to retain or assign tactical control of those units. It does not include authority to assign separate employment of components of the units concerned. Neither does it, of itself, include administrative or logistic control.’ NATO Glossary, above note 81, p. 2-O-3. While military forces generally use the same terminology, terms such as ‘full command’, ‘operational command’ and ‘operational control’ may have different meanings from one state to another or from one international organisation to another. The UN has a definition of ‘operational control’ which would be tantamount to ‘operational command’ within NATO's meaning. UN, Department of Peacekeeping Operations and Department of Field Support, Authority, Command and Control in UN Peacekeeping Operations, 15 February 2008, Ref. 2008.4, p. 4.

84 The issue is further complicated by the lack of consistency in state practice when attributing conduct within the framework of peace operations and by states’ different positions regarding who can qualify as a party to an armed conflict, for example during NATO operations. See Giorgio Gaja, Second Report on the Responsibility of International Organisations, International Law Commission, 56^th session, UN Doc. A/CN.4/541, p. 4. See also O. Engdahl, above note 4.

85 Attribution is an operation that consists in establishing a link between an act and a person or an entity considered to be its author. This operation is particularly delicate for collective entities such as states or international organisations which necessarily act through physical persons. The operation consists of two stages: the first stage makes it possible to connect an act (or several acts) to an individual, and the second stage determines whether the individual or group of individuals concerned performs a function within this collective entity with the result that the acts of these individuals can be interpreted as being those of the entity itself. See Ascensio, Hervé, ‘La responsabilité selon la Cour International de Justice dans l'affaire du génocide bosniaque’, in Revue Générale de Droit International Public, 2007/2, p. 288Google Scholar.

86 M. Zwanenburg, above note 78, p. 26.

87 Article 7 of the Draft Articles on the Responsibility of International Organisations (DARIO), adopted by the International Law Commission at its 63^rd session, in 2011, and submitted to the UN General Assembly as a part of the Commission's report covering the work of that session (A/66/10): Conduct of organs of a State or organs or agents of an international organisation placed at the disposal of another international organisation. ‘The conduct of an organ of a State or an organ or agent of an international organisation that is placed at the disposal of another international organisation shall be considered under international law an act of the latter organisation if the organisation exercises effective control over that conduct.’

88 See the article by Paolo Palchetti in this issue of the Review. See also Paolo Palchetti, ‘How Can Member States Be Held Responsible for Wrongful Actions Committed during Peace Operations Conducted by International Organisations?’, Proceedings of the 12^th Bruges Colloquium, International Organisations’ Involvement in Peace Operations: Applicable Legal Framework and the Issue of Responsibility, 20–21 October 2011, Collegium No. 42, Autumn 2012, College of Europe–ICRC, p. 100.

89 For a discussion of the test used to determine the attribution of action undertaken by non-state armed groups, see D. Akande, above note 44, pp. 57 ff.; Spinedi, Marina, ‘On the Non-Attribution of the Bosnian Serbs’ Conduct to Serbia’, in Journal of International Criminal Justice, Vol. 5, 2007, pp. 829–838Google Scholar; Milanovic, Marco, ‘State Responsibility for Genocide’, in European Journal of International Law, Vol. 17, No. 3, 2006, pp. 553–604Google Scholar; Cassesse, Antonio, ‘The Nicaragua and Tadic Tests Revisited in Light of the ICJ Judgment on Genocide in Bosnia’, in European Journal of International Law, Vol. 18, No. 4, 2007, pp. 649–668Google Scholar; Griebel, Jörn and Plücken, Milan, ‘New Developments Regarding the Rules of Attribution? The ICJ's decision in Bosnia v. Serbia’, in Leiden Journal of International Law, 2008, pp. 601–622Google Scholar.

90 ICTY, The Prosecutor v. Tadić, Case No. IT-94-1-A, Judgment (Appeals Chamber), 15 July 1999, para. 131. This approach has also been endorsed by the ICC in The Prosecutor v. Lubanga Dyilo, Case No. ICC 01/04-01/06, Decision on the Confirmation of Charges (Preliminary Chamber), 29 January 2007, para. 211.

91 ICJ, Application of the Convention on the prevention and punishment of the crime of genocide (Bosnia and Herzegovina v. Serbia and Montenegro), Judgment, 26 February 2007, ICJ Reports 2007, para. 404: ‘Insofar as the “overall control” test is employed to determine whether or not an armed conflict is international, which was the sole question which the Appeals Chamber was called upon to decide, it may well be that the test is applicable and suitable.’

92 Application of the ‘overall control’ test to determine the parties to an armed conflict when multinational forces are drawn into hostilities has been proposed by O. Engdahl, above note 4.

93 UN, Department of Peacekeeping Operations and Department of Field Support, Authority, Command and Control in UN Peacekeeping Operations, 15 February 2008, Ref. 2008.4, p. 24.

94 A caveat is a limitation, restriction or constraint placed by a nation on its military forces or civilian elements under international organisation command and control, or otherwise available to the international organisation, that does not permit the mission force commander to deploy or employ them fully in line with the approved plan of the operations.

95 This has been recognised explicitly by the UN, which even went further by stating that ‘it has been the long-established position of the United Nations, however, that forces placed at the disposal of the United Nations are “transformed” into a United Nations subsidiary organ and, as such, entail the responsibility of the organisation just like any other subsidiary organ, regardless of whether control exercised over all aspects of the operation was in fact “effective.”’ International Law Commission, Responsibility of International Organisations: Comments and Observations Received by International Organisations, 63^rd session, 2011, UN Doc. A/CN.4/637/Add. 1, p. 13.

96 R. D. Glick, above note 26, p. 98: ‘As a consequence of its command and control, the United Nations is deemed a party to armed conflict and thereby subject to the obligations of IHL. In contrast, as a consequence of their lack of control, troop contributing states are neither parties to the armed conflict nor directly responsible for the actions of the UN armed forces.’

97 Obviously, this presumption may be rebutted if it is demonstrated that the TCCs recurrently interfere in the chain of command to such an extent that the UN cannot be considered to have command and control over the operations. In these circumstances, under IHL only the TCCs and not the UN as such may be considered to be a party to the armed conflict. It is important to note that isolated, sporadic or limited instances of interference should not be sufficient to divest the international organisation in question of belligerent status but, in this case, even if the international organisation remains a party to the armed conflict, the violations of international law resulting from the TCCs’ interference should be attributed only to the TCCs since they have exerted effective control over the specific impugned act.

98 What was said in the preceding footnote also applies to AU peace operations.

99 The notion of dual attribution – i.e., the possibility that the same act could be simultaneously attributed to a state and to an international organisation – has been expressly recognised by the International Law Commission. Dual attribution might well be admitted in cases where it is not clear whether the peace forces are acting under the authority of the TCCs or the international organisation. Such situations may occur when both entities are formally entitled to exert their authority over the troops and when actions are undertaken by mutual agreement. See P. Palchetti, ‘How Can Member States…’, above note 88, pp. 102–103; Leck, Christopher, ‘International Responsibility in United Nations Peacekeeping Operations: Command and Control Arrangement and the Attribution of Conduct’, in Melbourne Journal of International Law, Vol. 10, 2009, pp. 12 ffGoogle Scholar.

100 This determination is based on a case-by-case approach taking into account the characteristics of each peace operation.

101 NATO, Allied Joint Doctrine, AJP-01 (D), December 2010, available at: www.gov.uk/government/uploads/system/uploads/attachment_data/file/33694/AJP01D.pdf. See also, NATO Allied Joint Doctrine for the Conduct of Operations, AJP-3 (B), March 2011, available at: www.cicde.defense.gouv.fr/IMG/pdf/20110316_np_otan_ajp-3b.pdf.

102 Ibid.

103 Ibid.

104 However, a so-called ‘either-or approach’ has been put forward as a means of determining the parties to an armed conflict in the context of peace operations. According to this approach, the party can be either the international organisation, under whose auspices the peace operation is undertaken, or the TCCs, but not both simultaneously. Debuf, Els, Captured in War: Lawful Internment in Armed Conflict, Pédone, 2013, p. 135Google Scholar. Debuf argues that armed forces can be under the effective control of either their national state or the international organisation. While she acknowledges the possibility of joint responsibility, she discards the potential existence of a ‘combined effective control’. However, she ignores the possible existence of the dual attribution in the context of peace operations, to which the International Law Commission refers. The International Law Commission has recognised the possibility that the same conduct could be simultaneously attributed to a state and to an international organisation (International Law Commission, UN Doc. A/CN.4/637/Add. 1, p. 18). This ‘either-or approach’ is also favoured by M. Zwanenburg, above note 78, p. 27, who underlines the fact that considering both the international organisation and the TCCs as parties to the armed conflict would lead to unreasonable results. Indeed, according to Zwanenburg, such a situation would mean applying two different regimes of IHL (international humanitarian treaty law and customary IHL) to the same military unit. However, the argument loses some relevance when one takes into account the fact that, during NATO operations, detention activities are generally carried out exclusively by TCCs and not by NATO itself. The point made by Zwanenburg is pertinent in the event of combined activities such as air operations but it is tempered by the consideration that many of the treaty-based rules governing the conduct of hostilities are generally also accepted as norms of customary law.

105 Under this option, one would distinguish between members of the NATO mission on the basis of their participation in the hostilities, with those not drawn into hostilities retaining their so-called ‘protected status’.

106 O. Engdahl, above note 4.

107 See, in particular, Daphna Shraga, ‘The United Nations as an Actor Bound by International Humanitarian Law’, in L. Condorelli et al. (eds), above note 26, p. 333; Paolo Benvenuti, ‘The Implementation of International Humanitarian Law in the Framework of UN Peace-Keeping’, in Law in Humanitarian Crises: How Can International Humanitarian Law Be Made Effective in Armed Conflicts?, Office for the Official Publications of the European Communities, Luxembourg, 1995, pp. 96 ff.; Claude Emanuelli, ‘Les forces des Nations Unies et le droit international humanitaire’ in L. Condorelli et al. (eds), above note 26, pp. 357 ff.; Kolb, Robert, Droit humanitaire et opérations de paix internationales, Bruylant, Brussels, 2006, pp. 57 ffGoogle Scholar. ; Marco Sassòli, ‘International Humanitarian Law and Peace Operations, Scope of Application rationae materiae’, paper submitted to the 31^st Round Table on Current Problems of International Humanitarian Law, above note 2, pp. 93–94; David, Eric and Salmon, Jean, Droit international public, Vol. 3, Presses Universitaires de Bruxelles, 2012, 26^th edition, pp. 728 ffGoogle Scholar.

108 See, for example, ICRC, ‘International Humanitarian Law and the Challenges of Contemporary Armed Conflicts’, above note 40, p. 10; S. Vité, above note 41, pp. 87–88.

109 ICJ, Military and Paramilitary Activities in and against Nicaragua (Nicaragua v. United States of America), Judgment, ICJ Reports 1986, para. 219.

110 ICTY, The Prosecutor v. Tadić, Case No. IT-94-1-T, Decision on the Defence Motion for Interlocutory Appeal on Jurisdiction (Appeals Chamber), 2 October 1995, para. 77.

111 ICC, The Prosecutor v. Lubanga Dyilo, Case No. ICC-01/04-01/06, Decision on the Confirmation of Charges (Pre-Trial Chamber I), 29 January 2007, para. 209. See also ICC, The Prosecutor v. Lubanga Dyilo, Case No. ICC-01/04-01/06, Judgment (Trial Chamber I), 14 March 2012, paras. 536 and 565.

112 See ICRC, ‘International Humanitarian Law and the Challenges of Contemporary Armed Conflicts’, above note 40, p. 10.

113 See footnote 107.

114 Françoise Hampson, ‘Afghanistan 2001–2010’, in E. Wilmshurst (ed.), above note 41, pp. 255–258.

115 E. Wilmshurst, in E. Wilmshurst (ed.), above note 41, p. 487: ‘International forces may also be involved in non-international armed conflicts, where they are fighting alongside the armed forces of a State within its territory against one or more organised armed groups. Although not without controversy, the better view is that such a conflict is indeed non-international, regardless of the international components of the multinational force.’

116 Kirsch, Philippe, ‘La Convention sur la sécurité du personnel des Nations Unies et du personnel associé’, in Emanuelli, Claude (ed.), Les casques bleus: policiers ou combattants, Wilson et Lafleur, Montreal, 1997, p. 56Google Scholar; V. Koutroulis, above note 26.

117 M. Zwanenburg, above note 1, p. 185.

118 This section addresses situations in which multinational forces have already become a party to an armed conflict. When peace missions are deployed in the context of an armed conflict, be it international or non-international, without being a party to it, the legal status of the peace mission's personnel is crystal clear from an IHL perspective: they benefit from the protection afforded by this body of law to civilians. When a peace mission is not acting as a belligerent, its entire personnel (i.e., including its military component) must therefore be regarded as civilians for the purposes of IHL.

119 Actually, ‘integrated peace operations’ are essentially carried out under the command and control of the UN (see, in this connection, United Nations Peacekeeping Operations: Principles and Guidelines, above note 1, p. 59).

120 When peace missions comprise solely a military component, the determination of the legal status of their personnel under IHL will be easier, insofar as it will depend upon the engagement of these peace forces in the armed conflict qua a party to it. Once they have become a party to an armed conflict, be it international or non-international in nature, all the military personnel lose their protection against direct attacks and become lawful targets under IHL.

121 It has been argued, on the contrary, in the context of the UN peace operation in the DRC (MONUSCO), in particular in the wake of Security Council Resolution 2098 (2013) establishing the so-called ‘Intervention Brigade’ within MONUSCO, that the military units of this UN mission should be distinguished according to the functions they perform. Only those engaged in actual fighting would be parties to the non-international armed conflict, whereas those involved in other tasks stopping short of combat operations would be regarded as civilians under IHL. For an overview of these arguments, see Bruce ‘Ossie’ Oswald, , ‘The Security Council and the Intervention Brigade: Some Legal Issues’, in ASIL Insights, Vol. 17, No. 15Google Scholar, 6 June 2013, available at: www.asil.org/insights/volume/17/issue/15/security-council-and-intervention-brigade-some-legal-issues.

122 Melzer, Nils, Interpretive Guidance on the Notion of Direct Participation in Hostilities under International Humanitarian Law, ICRC, Geneva, 2009Google Scholar (hereinafter ICRC Interpretive Guidance). See also ICRC, ‘International Humanitarian Law and the Challenges of Contemporary Armed Conflicts’, above note 40, pp. 42–45.

123 These two situations do not affect the police personnel's inherent right to self-defence. For instance, the use of force by police personnel in self-defence or in defence of others against violence prohibited under IHL lacks belligerent nexus. If self-defence against prohibited violence were to entail loss of protection against direct attack, this would have the absurd consequence of legitimising a previously unlawful attack. The use of necessary and proportionate force in such situations cannot therefore be regarded as direct participation in hostilities. See ICRC Interpretive Guidance, above note 123, p. 61.

124 According to this theory, civilians’ loss and recovery of protection against direct attack is contingent upon their direct participation in hostilities. In other words, the duration of the loss of protection against direct attack directly depends on the beginning and end of ‘direct participation in hostilities’. Melzer, Nils, ‘Keeping the Balance between Military Necessity and Humanity: a Response to Four Critiques of the ICRC's Interpretive Guidance on the Notion of Direct Participation in Hostilities’, in New York University Journal of International Law and Politics, Vol. 42, No. 3, Spring 2010, pp. 883 ffGoogle Scholar.

125 Lehnardt, Chia, ‘Peackeeping’, in Chesterman, Simon and Fisher, Angelina (eds), Private Security, Public Order: the Outsourcing of Public Services and Its Limits, Oxford University Press, Oxford, 2009, pp. 205–221CrossRefGoogle Scholar.

126 Åse Gilje Østensen, UN Use of Private Military and Security Companies, Practices and Policies, SSR Paper 3, DCAF, 2011, p. 15.

127 See ICRC Interpretive Guidance, above note 123, pp. 37–40.

128 D. Shraga, ‘The Secretary General's Bulletin…’, above note 61, pp. 358–359.

129 Section 1.1 of the 1999 UN Secretary-General's Bulletin reads as follows: ‘The fundamental principles and rules of international humanitarian law set out in the present bulletin are applicable to United Nations forces when in situations of armed conflict they are actively engaged therein as combatants, to the extent and for the duration of their engagement’ (emphasis added).

130 D. Shraga, ‘The Secretary General's Bulletin…’, above note 61, pp. 358–359.

131 The legal basis of this exception to the classic IHL regime applicable to organised armed forces such as multinational forces is not easy to identify. Since the special status of multinational forces under jus ad bellum has been often invoked by some people in order to tailor the legal framework governing peace operations (as explained above), it is conceivable that the same argument could be made to justify a narrow interpretation of the temporal scope of application of IHL when multinational forces are engaged in armed conflict. However, it is submitted that the special legal status of peace forces under jus ad bellum can in no way lead to an interpretation of IHL norms running contrary to one of the basic principles of IHL, namely that of the equality between belligerents. Jus ad bellum arguments cannot be used to interpret narrowly the temporal scope of application of IHL.

132 ICC, The Prosecutor v. Abu Garda, Case No. ICC 02/05-02/09, Decision on the Confirmation of Charges (Pre-Trial Chamber I), 8 February 2010, paras. 78 ff, in particular para. 83, which states: ‘The Majority concludes that, under the Statute, personnel involved in peacekeeping mission enjoy protection from attacks unless and for such time as they take a direct part in hostilities or in combat-related activities’; ICC, The Prosecutor v. Abdallah Banda et al., Case No. ICC 02/05-03/09, Decision on the Confirmation of Charges (Pre-Trial Chamber), 7 March 2011, paras. 61 ff.

133 Special Court for Sierra Leone (SCSL), The Prosecutor v. Hassan Sasay, Case No. SCSL 04-15-T, Judgment (Trial Chamber), 2 March 2009, para. 233: ‘In the Chamber's view, common sense dictates that peacekeepers are considered to be civilians only insofar as they fall within the definition of civilians laid down for non-combatants in customary international law and under Additional Protocol II as discussed above – namely, that they do not take a direct part in hostilities. It is also the Chamber's view that by force of logic, personnel of peacekeeping missions are entitled to protection as long as they are not taking a direct part in the hostilities – and thus have become combatants – at the time of the alleged offence. Where peacekeepers become combatants, they can be legitimate targets for the extent of their participation [in the hostilities] in accordance with international humanitarian law.’

134 Under IHL, the concepts of civilians and armed forces are mutually exclusive. For instance, the ICTY defined civilians as ‘persons who are not, or no longer, members of armed forces’ (ICTY, The Prosecutor v. Blaskic, Case No. IT-95-14-T, Judgment (Trial Chamber), 3 March 2000, para. 180).

135 As discussed above.

136 With all the consequences this entails for the peace mission personnel's loss of protection against direct attack.

137 The end of armed conflict does not mean that international humanitarian law will cease to apply entirely. Some specific provisions will survive after the end of armed conflict, in particular those dealing with persons whose final release, repatriation or re-establishment takes place thereafter. These persons continue to benefit from the relevant provisions of the Conventions and the Protocols thereto until their final release, repatriation or re-establishment.

138 This notion of general close of military operations was interpreted in the ICRC commentary of 1958 as the ‘final end of all fighting between all those concerned’. Pictet, Jean (ed.), Commentary on the Geneva Conventions of 12 August 1949, Vol. IV, Geneva Convention relative to the Protection of Civilian Persons in Time of War, ICRC, Geneva, 1958, p. 62Google Scholar. Later on, in the ICRC commentary on Additional Protocol I, it was argued that the expression ‘general close of the military operations’ means something more than the mere cessation of active hostilities since military operations of a belligerent nature do not necessary imply armed violence and can continue despite the absence of hostilities. Sandoz, Yves, Swinarski, Christophe and Zimmermann, Bruno (eds), Commentary on the Additional Protocols, ICRC, Geneva, 1987, p. 68Google Scholar. In this connection, one can infer that the general close of the military operations would include not only the end of active hostilities, but also the end of military manoeuvres of a bellicose nature, so that the likelihood of the resumption of hostilities can be reasonably ruled out.

139 See above.

140 For a summary of these arguments, see Tristan Ferraro, ‘The Geographical Reach of IHL: the Law and Current Challenges’, Proceedings of the 13^th Bruges Colloquium, above note 6, pp. 105–113. However, this author does not share such restrictive views.

141 It is generally agreed that in a situation of international armed conflict, irrespective of the involvement of multinational forces therein, IHL applies to the whole territory of the belligerents. See for example D. Fleck, above note 41, pp. 39–51; Y. Dinstein, above note 15, p. 19.

142 Moir, Lindsay, The Law of Internal Armed Conflict, Cambridge University Press, Cambridge, 2002, p. 31Google Scholar. A major source cited in support of this view is the ICRC's Commentaries on the Geneva Conventions, in which Jean Pictet unequivocally states that the Article applies to a non-international conflict occurring within the territory of a single state. See, for example, Pictet, J. (ed.), Commentary on the Geneva Conventions of 12 August 1949, Vol. IV, Geneva Convention relative to the Protection of Civilian Persons in Time of War, ICRC, Geneva, 1958, p. 36Google Scholar : ‘Speaking generally, it must be recognised that the conflicts referred to in Article 3 are armed conflicts, with armed forces on either side engaged in hostilities – conflicts, in short, which are in many respects similar to an international war, but take place within the confines of a single country.’

143 ICTR, The Prosecutor v. Musema, Case No. ICTR-96-13-A, Judgment (Trial Chamber), 27 January 2000, paras. 247–248.

144 For an overview of the drafting history of Common Article 3, see Cullen, Anthony, The Concept of Non-International Armed Conflict in International Humanitarian Law, Cambridge University Press, Cambridge, 2010CrossRefGoogle Scholar.

145 Ibid., pp. 140–142.

146 For example, Common Article 3 of the Geneva Conventions provides: ‘The following acts are prohibited at any time and in any place whatsoever’. Even if less explicit, other provisions such Article 6(2) of Geneva Convention IV, Article 3(b) of Additional Protocol I and Article 2(6) of Additional Protocol II tend to favour a broad interpretation of the geographical scope of application of IHL. In addition, it is worth noting that Article 49(2) of Additional Protocol I, dealing with the notion of attacks, implies that attacks may be conducted throughout the territory of the parties to an armed conflict. The ICTY stated in this regard that ‘The geographical and temporal frame of reference for internal armed conflicts is similarly broad. This conception is reflected in the fact that beneficiaries of common Article 3 of the Geneva Conventions are those taking no active part (or no longer taking an active part) in the hostilities. This indicates that the rules contained in Article 3 also apply outside the narrow geographical context of the actual theatre of combat operations. Similarly, certain language in Protocol II to the Geneva Conventions also suggests a broad scope. First, like common Article 3, it explicitly protects “[a]ll persons who do not take a direct part or who have ceased to take part in hostilities.” … Article 2(1) provides: “[t]his Protocol shall be applied … to all persons affected by an armed conflict as defined in Article 1.” The same provision specifies in paragraph 2 that: “[A]t the end of the conflict, all the persons who have been deprived of their liberty or whose liberty has been restricted for reasons related to such conflict, as well as those deprived of their liberty or whose liberty is restricted after the conflict for the same reasons, shall enjoy the protection of Articles 5 and 6 until the end of such deprivation or restriction of liberty.” … The relatively loose nature of the language “for reasons related to such conflict”, suggests a broad geographical scope as well. The nexus required is only a relationship between the conflict and the deprivation of liberty, not that the deprivation occurred in the midst of battle.’ ICTY, The Prosecutor v. Tadić, Decision on the Defence Motion for Interlocutory Appeal on Jurisdiction (Appeals Chamber), 2 October 1995, para. 69.

147 ICTY, The Prosecutor v. D. Tadić, Interlocutory Appeal on Jurisdiction (Appeals Chamber), paras. 67 and 70; ICTY, The Prosecutor v. Kunarac, Kovac, and Vokovic, Judgment (Appeals Chamber), 12 June 2002, para. 57; ICTR, The Prosecutor v. Akayesu, Judgment (Trial Chamber), 2 September 1998, paras. 635–636; Special Court for Sierra Leone, The Prosecutor v. Brima, Kamara and Kanu, Case No. SCSL 04-16-T, Judgment (Trial Chamber II), 20 June 2007, para. 245; ICC, The Prosecutor v. Lubanga Dyilo, Case No. ICC-01/04-1/06, Judgment (Trial Chamber I), 14 March 2012, para. 533.

148 ICTR, The Prosecutor v. Semanza, Judgment (Trial Chamber), 15 May 2003, para. 367.

149 This narrow approach is reflected in recent advice to the Government, the House of Representatives and the Senate of the Netherlands by the Advisory Committee on Issues of Public International Law, which noted that in non-international armed conflicts, international humanitarian law ‘applies only to the territory of the State where a conflict is taking place’. Advisory Committee on Issues of Public International Law, main conclusions of advice on armed drones, The Hague, July 2013.

150 S. Vité, above note 41, pp. 87–92; ICRC, ‘International Humanitarian Law and the Challenges of Contemporary Armed Conflicts’, above note 40, pp. 9–10. Furthermore, Articles 1 and 7 of the Statute of the ICTR extend the tribunal's jurisdiction over the enforcement of the law of non-international armed conflicts to Rwanda's neighbouring countries. This confirms that the IHL applicable to a non-international armed conflict is not restricted to the territory of one single state and extends to the territory of contiguous non-belligerent countries.

151 Pejic, Jelena, ‘The Protective Scope of Common Article 3: More than Meets the Eye’, in International Review of the Red Cross, Vol. 93, No. 881, March 2011, p. 199CrossRefGoogle Scholar.

152 Arimatsu, Louise, ‘Territory, Boundaries and the Law of Armed Conflict’, in Yearbook of International Humanitarian Law, Vol. 12, 2009, p. 178Google Scholar; Kretzmer, David, ‘Targeting Killings of Suspected Terrorists: Extra-Judicial Executions or Legitimate Means of Defence?’, in European Journal of International Law, Vol. 16, No. 2, 2005, p. 195Google Scholar; Lubell, Noam, Extraterritorial Use of Force against Non-State Actors, Oxford University Press, Oxford, 2010, p. 104Google Scholar; Ratner, Steven, ‘Predator and Prey: Seizing and Killing Suspected Terrorists Abroad’, in Journal of Political Philosophy, Vol. 15, No. 3, 2007, p. 261Google Scholar; Kleffner, Jann, ‘Scope of Application of International Humanitarian Law’, in Fleck, Dieter et al. , The Handbook of International Humanitarian Law, Oxford University Press, 2013, pp. 56–57Google Scholar; Mangezi, Mutsa, ‘Localised Armed Conflicts: a Factual Reality, a Legal Misnomer’, in African Yearbook on International Humanitarian Law, 2012, p. 84Google Scholar; Marco Sassòli, ‘Transnational Armed Groups and International Humanitarian Law’, Program on Humanitarian Policy and Conflict Research, Harvard University, Occasional Paper Series, No. 6, Winter 2006, pp. 8–9. See also Maj. Sean Condron (ed.), U.S. Operational Law Handbook, The Judge Advocate General Legal Center and School, US Army, Charlottesville, 2011, p. 156: ‘the scope of [non-international armed conflict] has expanded to include conflicts not contained within the boundaries of a single state’.

153 Lubell, Noam and Derejko, Nathan, ‘A Global Battlefield? Drones and the Geographical Scope of Armed Conflict’, in Journal of International Criminal Justice, Vol. 11, No. 1, March 2013, p. 70CrossRefGoogle Scholar; M. Mangezi, above note 152, p. 84.

154 If the attacks were directed at civilians or civilian objects, they would be criminal and open to prosecution as such under IHL, as well as a war crime. In addition, such action would certainly be criminalised under the affected state's domestic law. A broad interpretation of the territorial scope of IHL does not mean that each and every incident or use of force involving multinational forces is governed by IHL. Only action having a clear nexus with the ongoing multinational non-international armed conflict and the related hostilities will be subject to IHL rules.