Intervention: When, Why and How?

Written evidence from Dr Arman Sarvarian, Lecturer in Law, University of Surrey and Director, Surrey International Law Centre

1. This is a submission of written evidence in response to the call published by the House of Commons Defence Select Committee ('the Committee') concerning its inquiry on ‘Intervention: Why, When and How?’ The main questions of the inquiry are: 1) what is the strategic thinking behind UK intervention strategy; and 2) What should intervention be used for? This submission made in my personal capacity as an academic lawyer specialising in public international law.

2. I have submitted this evidence in order to assist the inquiry in its examination of the role played by legality in the strategy of the Government in armed interventions. It consequently focuses upon the following sub-themes of the inquiry: 1) The legitimacy of intervention (legality and political and public support (including communication strategies)); 2) The implications of Treaty and international obligations; and 3) How are decisions to intervene taken? Although this submission is intended to outline the legal issues arising from armed intervention, it focuses upon the abortive humanitarian intervention in Syria as its principal case study. In particular, it illustrates the important role played by the House of Commons in its defeat of the Government motion of 29 August 2013 [1] not only in the decision by the Government not to intervene but also for the future development of the law of humanitarian intervention.

3. Whilst based upon a draft paper concerning the legal consequences of the abortive humanitarian intervention in Syria by the United States of America and its allies – in particular, the implications for the legal position of the UK on the lawfulness of humanitarian intervention – the submission has been tailored to address the terms of reference for this inquiry. It addresses: 1) the use of force in international law; 2) the legality of the abortive Syrian intervention; and 3) assessing the United Kingdom legal position on humanitarian intervention. A summary of conclusions and recommendations is provided at the end of the submission.

The lawfulness of the doctrine of humanitarian intervention

The use of force in international law

4. The principal source of international law on the use of force is the Charter of the United Nations 1945. This provides for a general prohibition on the use of force in international relations [2]   and a corresponding duty to resolve international disputes through peaceful means (e.g. - negotiation, mediation, arbitration or adjudication). [3] The general ban is subject to two express exceptions: 1) authorisation of 'forcible measures' by the UN Security Council under Article 42 of the Charter; and 2) individual or collective self-defence under Article 51 of the Charter.

5. The UN collective security system charges the Security Council with 'primary responsibility for the maintenance of international peace and security', for which purpose the Member States 'agree that in carrying out its duties under this responsibility the Security Council acts on their behalf.' [4] Whilst the Security Council is the primary actor in international peace and security, it is not the exclusive actor. The UN General Assembly has claimed the power to act to restore international peace and security where, due to a permanent member veto in the Security Council (as opposed to a collective decision not to act in which the veto is not exercised), the Security Council is incapable of doing so. [5] The 'Uniting for Peace' procedure has been invoked on ten occasions, most recently in relation to the occupied Palestinian territories in 2003. Despite initial objections in the 1950s (especially by the Soviet Union) its lawfulness has subsequently been accepted in practice [6] and affirmed by the International Court of Justice as the primary judicial organ of the United Nations. [7]

Humanitarian intervention as customary international law

6. Although the doctrine of humanitarian intervention has a long lineage in international law scholarship, [8] it was only in the 1990s that States began to consider it as an alternative legal basis for the use of force. [9] In a gradual shift from initial scepticism to strong support in the early 1990s, the United Kingdom has asserted that in the event of a veto in the Security Council individual States may unilaterally use force, subject to certain conditions, to alleviate a compelling and urgent situation of extreme humanitarian distress demanding immediate relief. Whilst the United Kingdom invoked this doctrine in relation to Operation Haven concerning the protection of Iraqi Kurds in the 1990s, the United States of America did not do so, relying instead upon implied authorisation by Security Council Resolution 1996.

7. Even if the Article 103 problem is disregarded, as the Charter itself provides no basis the doctrine of humanitarian intervention must still gain acceptance as a norm of customary international law [10] by the international community of States. To render a purported application of humanitarian intervention lawful, it must have gained general acceptance prior to the occasion in which it is invoked. Consequently, it is necessary to analyse the development of the doctrine in the years preceding the Syrian case in 2013 to determine whether it had been accepted as law.

8. The aerial bombardment undertaken by NATO Member States in Kosovo in 1999 tested the legality of humanitarian intervention. Amongst NATO Member States, only the United Kingdom and Belgium invoked the doctrine to justify their uses of force. [11] Other NATO Member States not only did not invoke it in the Legality on the Use of Force Cases before the International Court of Justice but some (e.g. - Germany and the United States of America) argued that the operation was not to be seen as a precedent for future action. [12] The reaction amongst Russia, China and the Non-Aligned Movement Member States to intervention without Security Council authorisation was overwhelmingly hostile. [13]

9. In the United Kingdom, the question of legality was central. Although the Government asserted that the doctrine of humanitarian intervention provided a legal basis for the operation by having gained prior acceptance by the international community of States as a norm of customary international law, in its inquiry into the legality of the operation the Foreign Affairs Select Committee of the House of Commons concluded: 1) at the very least, the doctrine of humanitarian intervention has a tenuous basis in current international customary law, and that this renders NATO action legally questionable; and 2) NATO's military action, if of dubious legality in the current state of international law, was justified on moral grounds. [14] These conclusions were reached with the benefit of evidence from highly distinguished international lawyers. [15]

10. In the 2000s, the emergence of the Canadian-inspired 'responsibility to protect' political doctrine saw a renewed emphasis placed upon the UN collective security system and the doctrine of humanitarian intervention dropped from the international agenda. [16] In the practice of the past six years the Security Council was the forum for deciding whether to undertake collective security action, most notably in the case of Libya (2011). [17] Until the Syrian example of 2013, there was no attempt after Kosovo to invoke the doctrine of humanitarian intervention to justify an armed intervention.

The problem of Article 103

11. In assessing the lawfulness of the doctrine, an important point is that Article 103 of the Charter provides: 'In the event of a conflict between the obligations of the Members of the United Nations under the present Charter and their obligations under any other international agreement, their obligations under the present Charter shall prevail.' This priority clause provides for the resolution of conflicts of obligations for States. [18] Its significance is to legally entrench the primacy of the collective security system of the United Nations, including the general prohibition of the use of force.

12. The legal problem that this presents for proponents of unilateral humanitarian intervention is that, even if the doctrine were to be accepted by the international community, Article 103 obliges States to prioritise the Charter rules on the use of force outlined above. To remove this impediment, amendment to the UN Charter would be required. The United Kingdom has invoked Article 103 on several occasions to excuse breaches of human rights obligations due to the need were to implement overriding obligations deriving from UN Security Council decisions. [19]

Assessing the legal position of the United Kingdom

13. As indicated above, since the early 1990s the United Kingdom has been the leading proponent of the doctrine of humanitarian intervention. However, its efforts to persuade the international community of States to accept the legality of the doctrine have proved to be unsuccessful. Although the state of international law at the time of the proposed Syria operation rejected the doctrine, the abortive operation nevertheless presents a fresh opportunity to assess the legal position of the United Kingdom and other States with reference to the two criteria for customary international law: 1) State practice; and 2) opinion as to law (opinio iuris).

14. Unlike in national legal systems, public international law lacks for most legislative purposes a centralised authority. In its centrifugal system, the primary legislators are States which make law by two principal means: 1) treaties; and 2) custom. Whereas treaties are concluded through relatively clear forms, [20] custom remains a crude instrument. In 2012, the International Law Commission [21] decided to include the topic ‘Formation and evidence of customary international law’ in its programme of work. In light of the importance of the work of the Commission, [22] this indicates both the importance of the topic and its underdeveloped state.

15. Practice can be generated by any organ of a State, in particular by those with competence in the subject-matter of the rule concerned. [23] For example, a resolution by the London Borough of Islington regarding the doctrine of humanitarian intervention would not manifest the practice of the UK in light of that State organ’s lack of competence in foreign affairs. By contrast, the note published by the Office of the Prime Minister [24]   on 29 August 2013 (entitled 'Chemical weapon use by the Syrian regime: UK government legal position') and incorporated into the statement by the Prime Minister in the House of Commons on 29 August 2013. [25] However questionable in quality, that summary constitutes relevant practice for the purpose of defining the legal position of the UK - as does the vote of the House of Commons.

16. The criterion of opinio iuris entails a subjective expression by a State of its legal position. This can either entail a view as to the State of the law today or an opinion as to what the law ought to be tomorrow. Leaving to one side the paradoxes well-known to international lawyers in this field, the prominence of the question of the legality of humanitarian intervention in the Government motion, Opposition amendment and debate in the House, in my view, renders the votes of the House an expression of opinio iuris for the purpose articulating the legal position of the United Kingdom. The problem created thereby is that the decision of the House rejecting the Government motion necessarily creates an inconsistency between the long-held Government legal position on humanitarian intervention and the newly-expressed view of the House.

17. The note published by the Office of the Prime Minister ('the Note') does not constitute legal advice in the true sense of the term, namely, as an independent opinion produced by a lawyer who accepts professional responsibility for it.  It is not signed by the Attorney General and is not attributed to him. It is consequently best-treated as the collective view of the Cabinet, or alternatively as the individual view of the Prime Minister. Although it is not clear to what degree the Note is based upon legal advice provided by the Attorney, its value as a definitive statement of the legal position of the United Kingdom is diminished by the fact that the Attorney (unlike in the case of Lord Goldsmith concerning Iraq) did not undertake personal responsibility for it through a ministerial statement to the House of Commons. [26]

18. In the Note, the Government expressly based the legality of its proposed armed intervention in Syria upon humanitarian intervention. [27] The Note asserts: 'If action in the Security Council is blocked, the UK would still be permitted under international law to take exceptional measures in order to alleviate the scale of the overwhelming humanitarian catastrophe in Syria by deterring and disrupting the further use of chemical weapons by the Syrian regime.' [28]

19. The Note contains neither analysis of international law nor underpinning for its bald assertion that 'under international law' the doctrine of humanitarian intervention is lawful. This lack of substantiation further devalues the Note as an authoritative statement of the legal position of the country. Whilst additional problems arise concerning the assertion that the criteria set out for humanitarian intervention applied to the facts of the Syrian scenario, this is not the focus of this evidence.

20. The Note was cited by the Prime Minister in proposing his motion to the House of Commons on 29 August 2013. The motion to the House, inter alia: ‘Notes that the use of chemical weapons is a war crime under customary law and a crime against humanity, and that the principle of humanitarian intervention provides a sound legal basis for taking action’. [29] In his statement, the Prime Minister asserted: ‘We have a summary of the Government’s legal position, which makes it explicit that military action would have a clear legal basis.’ [30] A number of interventions and responses in the debate addressed the question of legality. [31] It is clear that legality was not secondary or peripheral to the vote but, to the contrary, was a core issue at the forefront of the debate. Concordantly, this enhances the legal value of the decision of the House to reject the lawfulness of the principle of humanitarian intervention.

21. The constitutional position suggests that the House of Commons vote does not have the effect of defining the legal position of the United Kingdom on humanitarian intervention. As the Royal Prerogative on uses of force remains intact, it was open to the Government to proceed with its own view concerning the lawfulness of humanitarian intervention in its exercise of the Prerogative. On this approach, notwithstanding the political import of the vote of the House, it is per se valueless for the purpose of stating the legal position of the country.

22. However, the constitutional position appears to be qualified by an emerging convention that the House of Commons be consulted prior to taking military action. Moreover, on this specific occasion, the significance of the vote is enhanced by the decision of the Government to not exercise the prerogative in response:

‘Let me say that the House has not voted for either motion tonight. I strongly believe in the need for a tough response to the use of chemical weapons, but I also believe in respecting the will of this House of Commons. It is very clear tonight that, while the House has not passed a motion, the British Parliament, reflecting the views of the British people, does not want to see British military action. I get that, and the Government will act accordingly.’ [32]

This suggests that, in practice, the vote does carry normative weight in the exercise of the Royal Prerogative. This weight was linked to the electoral mandate of the House of Commons, which imbues its collective will with magnified importance.

23. At present, it is too soon to reach a definitive conclusion concerning whether the legal position of the United Kingdom has in fact changed. Although the constitutional position is that the Royal Prerogative may be exercised regardless of the view of the House of Commons, the particular circumstances of this vote vested it with such persuasive weight such that the Government chose to respect the will of the House concerning the lawfulness of humanitarian intervention. Consequently, it appears the legal position of the United Kingdom on humanitarian intervention is changing: whereas the country has supported the doctrine since Kosovo, it will no longer do so.

24. The implication of this conclusion is that the Government will cease to support the principle of humanitarian intervention in its conduct of foreign affairs in the United Nations and elsewhere. Although it is formally open to the Government to pursue its own legal position, its undertaking to ‘respect the will of [the] House of Commons’ and the invidious inconsistency of ignoring the vote in its future position on humanitarian intervention render such a course inadvisable. At the least, the credibility of its legal position in relation to other States would be undermined by the fact that the House of Commons is on record as adopting a contrary position.

Executive summary of conclusions and recommendations

25. In assessing the legality of the abortive armed intervention in Syria, this analysis offers the following conclusions. First, evaluation of State practice in the two decades preceding 29 August 2013 shows that humanitarian intervention had clearly been rejected by the international community. In particular, fallout from the principal precedent of Kosovo shows that not only were NATO Member States disunited on the question but the wider international community rejected the legal case put forward by the United Kingdom. In addition, the majority of international lawyers in the United Kingdom considered the intervention to have been unlawful.

26. Second, even if humanitarian intervention had been customary international law, the Article 103 would have displaced it by giving priority to the collective security system provided by the UN Charter, including the general prohibition on the use of force in international relations.

27. Third, based upon the first two conclusions, the lack of a legal basis for the proposed armed intervention in Syria would have rendered such an operation an unlawful use of force.

28. Fourth, though it is too early to make a definitive assessment, the Government's acceptance of the will of the House of Commons appears to be changing the legal position of the United Kingdom with respect to the lawfulness of humanitarian intervention.

29. In addition, I propose the following recommendations for adoption in the Committee's report. First, the renunciation of the doctrine of humanitarian intervention by the Government in its conduct of foreign affairs. Pragmatically, the continued promotion of the doctrine is arguably not tenable in light of its rejection by the House of Commons. Furthermore, the circumvention of the UN system entailed in humanitarian intervention is inconsistent with the United Kingdom's invocation of Article 103 in order to assert the primacy of Security Council decisions.

30. Second, the adoption of a policy to utilise the General Assembly 'Uniting for Peace' procedure where a veto in the Security Council frustrates an attempt to intervene on humanitarian grounds. Not only is this procedure recognised as lawful but it provides an invaluable basis of multilateral consent and cooperation for the conduct of humanitarian intervention. By persuading a majority of the international community of States to endorse the proposed intervention, a clear foundation can be provided not only for the lawfulness of the operation but also for its support by the House of Commons and the country.

10 January 2014


[1] Although the vote of the House on the Opposition amendment is also relevant, this submission focuses upon the vote of the Government motion as it directly pertains to its central issue of divergent Government and House of Commons positions on legality.

[2] Charter, Art. 2(4). See further Corfu Channel Case (United Kingdom v. Albania) ICJ Rep. (1949) 4, 34; Military and Paramilitary Activities in and around Nicaragua (Nicaragua v. United States of America) ICJ Rep. (1986) 14, para. 202. For detailed commentary of each Charter provision cited in this submission, see Simma et al. (Eds), The Charter of the United Nations: a Commentary (2012).

[3] Charter, Arts 2(3), 33(1).

[4] Charter, Art. 24(2).

[5] UN General Assembly Resn 377A ('Uniting for Peace'), 3 November 1950.

[6] Binder, 'Uniting for Peace Resolution (1950)', Max Planck Encyclopaedia of Public International Law (August 2006), para.23.

[7] Legal Consequences of the Construction of a Wall in Occupied Palestinian Territory (Advisory Opinion) ICJ Rep. (2004), 136, paras 26-32.

[8] Brownlie, International Law and the Use of Force by States (1963), 338-347.

[9] Gray, International Law and the Use of Force (2008), 35-37.

[10] In addition to treaties, custom is the second main source of international law - Art.38(1) Statute of the International Court of Justice 1945. The two well-known criteria for the formation of customary law are: 1) the practice of States; and 2) the legal opinions or positions of States (opinio iuris sive necessitatis). Crudely put, the former criterion entails ‘what States have done’ whereas the latter concerns ‘why (legally) States have done it’. The formation of a customary rule is necessarily a retrospective exercise: to determine whether a customary rule exists, international courts, scholars and others examine the precedents of State practice to distil whether the rule commands sufficient support amongst States.

[11] Ibidem, 42, 45.

[12] Ibidem, 47.

[13] Ibidem, 52.

[14] House of Commons Foreign Affairs Select Committee Fourth Report (23 May 2000), 132, 138.

[15] Professor Christopher Greenwood QC of the London School of Economics, Mr Mark Littman QC, Professor Vaughan Lowe of Oxford University, Professor Ian Brownlie QC (Oxford University), Professor Christine Chinkin (University of Michigan), Professor Peter Rowe (Lancaster University)and Professor Bruno Simma (Ludwig-Maximilians-Universität, Munich). The Attorney General declined to submit evidence on 'a matter as sensitive as this', citing the confidentiality of Law Officers' advice to Government. The submissions were published in volume 49, issue 4 (2000) of the International and Comparative Law Quarterly. See also, e.g. - Wheatley, 'The Foreign Affairs Select Committee Report on Kosovo: NATO Action and Humanitarian Intervention', 5(1) Journal of Conflict and Security Law (2000), 261-273; La primarité des droits de l'homme: licéité ou illicéité de l'intervention humainitaire' and Flauss, la primarité des droits de la personne: licéité ou illicéité de l'intervention humainitaire' in Tomuschat (Ed.), Kosovo and the International Community: A Legal Assessment (2002), 65-102.

[16] Simma, supra note 2, 1207-1210, 1225, 1230.

[17] Ibidem, 1216-1218.

[18] See further 'Fragmentation of International Law: Difficulties arising from the Diversification and Expansion of International Law', Report of the Study Group of the International Law Commission (April 2006), UN Doc. A/CN.4/L.682 168-173.

[19] E.g. - App.No.27021/08 al-Jedda v. United Kingdom (2011) 53 E.H.R.R. 23, paras 87-92; Case C-402/05 Yassin Abdullah Kadi and Al Barakaat International Foundation v. Council of the European Union and Commission of the European Communities [2008] European Court Reports I-06351, para. 276.

[20] See the Vienna Convention on the Law of Treaties 1969, Part II.

[21] The International Law Commission is a committee of experts created in 1947 by the UN General Assembly to work for ‘the promotion of the progressive development of international law and its codification’.

[22] It has been instrumental in the inspiration of a number of important treaties and other works of international law, such as the Vienna Convention on the Law of Treaties 1969, the United Nations Convention on the Law of the Sea 1982, the Statute of the International Criminal Court 1998 and the Articles on the Responsibility of States for Internationally Wrongful Acts 2002.

[23] Examples of practice include: diplomatic correspondence, policy statements, press releases, opinions of government legal advisers, official manuals on legal questions, comments by government on ILC drafts, national legislation and international and national judicial decisions. See, e.g. – Crawford, Brownlie’s Principles of Public International Law (2012), 24.

[24] https://www.gov.uk/government/publications/chemical-weapon-use-by-syrian-regime-uk-government-legal-position.

[25] HC Deb, 29 August 2013, col. 1426.

[26] The first question in the House of Commons debate was 'why [the Prime Minister] has refused to publish the Attorney-General's full advice' - HC Deb, 29 August 2013, col. 1426. The Prime Minister replied: 'There had been a long-standing convention, backed by Attorney-Generals of all parties and all Governments, not to publish any legal advice at all. This Government changed that. With the Libya conflict, we published a summary of the legal advice. On this issue, we have published a very clear summary of the legal advice and I urge all right hon. and hon. Members to read it.'

[27] Supra note 25, para. 2.

[28] Ibidem, para. 4.

[29] HC Deb, 29 August 2013, col 1426.

[30] Ibidem.

[31] Ibidem, cols 1426-1427, 1429, 1434-1435, 1438-1439, 1441, 1443-1444, 1447, 1453-1455, 1458, 1460, 1462.

[32] HC Deb, 29 August 2013, col 1556.

Prepared 10th January 2014