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16 Implementation of International Humanitarian Law

David Turns

From: The Oxford Guide to International Humanitarian Law

Edited By: Ben Saul, Dapo Akande

From: Oxford Public International Law (http://opil.ouplaw.com). (c) Oxford University Press, 2021. All Rights Reserved.date: 10 May 2021

Armed conflict — National implementation

(p. 359) 16  Implementation of International Humanitarian Law

1.  Introduction

It is something of a truism to say that legal rules are not worth the paper they are written on if they are not enforced. In the second decade of the twenty-first century there is a striking contrast between the apparent inability—or unwillingness—of the world’s nations to properly implement and enforce the rules of international humanitarian law (‘IHL’) and the manifold methods by which such implementation and enforcement may be achieved. On one level this might be viewed as resulting in part from, on the one hand, the accelerated development of the law itself since 1945, and on the other, from the very high levels of media and public interest in the conduct of the various actors in situations of armed conflict. This interest is spurred on by the omnipresence of social media and ever-increasing round-the-clock media scrutiny of military operations, particularly where (as is almost invariably the case, to a greater or lesser extent) these involve civilian casualties; but it is also the case that the law itself provides for its own implementation and enforcement in a multiplicity of ways. These arise under IHL itself and also under various other specific legal regimes within the broad framework of public international law; they address the duties and liabilities of States and also of individuals; they are judicial and quasi-judicial in nature, and also political; and they require action at the national, as well as at the regional and universal, levels. Usually, the action that is required to give effect to these various legal mechanisms is comparatively clear and straightforward. In theory, therefore, one might be forgiven for assuming that the implementation of IHL should be a matter of no great controversy.

And yet, four brief vignettes of recent topical situations suffice to illustrate the difficulties that are encountered in practice when states, international organizations, and non-governmental organizations (NGOs) seek to do nothing more than secure greater observance of this body of law to which, after all, every sovereign state in the world is at least formally and voluntarily committed to.

  • •  Following the United Nations High Commissioner for Human Rights’ recommendation for the establishment of ‘prompt, thorough, effective, independent and impartial investigations into … alleged violations of international humanitarian law’ committed by both sides in the Yemeni Civil War,1 the Netherlands sponsored a draft resolution in the Human Rights Council (HRC) which would have mandated a UN mission to (p. 360) Yemen in order to establish facts and document violations by both the Houthi forces currently in control in Sana’a and the Saudi-led regional coalition that has been intervening in support of the internationally recognized government in Aden since March 2015.2 However, in the face of intense Saudi pressure and open hostility on the part of other Arab members of the coalition, as well as conspicuous lack of support from various other countries in the HRC, including the US and the UK, the Dutch draft—negotiations on which had also been boycotted by the Yemeni Government in the HRC—was withdrawn3 and a much weaker Arab-drafted resolution, calling merely for ‘technical assistance’ to support a domestic investigative committee in Yemen and the reporting already taking place, was adopted by consensus.4 A Group of International and Regional Eminent Experts on Yemen appointed by the HRC has reported on ‘patterns of continued violations by all parties to the conflict’, but to date no action has been taken to end the impunity noted in the Experts’ report.5

  • •  On 3 October 2015, a US Special Forces airstrike provided by way of close air support in response to a request from Afghan National Army personnel on the ground in Kunduz in northern Afghanistan, which had recently been retaken by Taliban fighters, hit a hospital operated by the humanitarian organization Médecins Sans Frontières (MSF), killing thirty civilians (MSF staff and patients) and wounding thirty-seven more.6 An internal US military investigation’s findings were summarized in the following terms: ‘the approximate cause of this tragedy was a direct result of avoidable human error compounded by process and equipment failures … some of the US individuals involved did not follow the rules of engagement. With regard to … proportionality … the actions of the aircrew and the Special Operations Forces were not appropriate to the threats that they faced.7 Although sixteen US military personnel were suspended and other investigations were undertaken by the North Atlantic Treaty Organization (NATO) Command in Afghanistan and the Afghan national authorities, nobody has been charged with any offences in relation to the incident and the lack of any reference to possible criminal investigations was criticized by the NGO Human Rights Watch (HRW)8 as well as by MSF itself.9

  • •  Although the Agreement on the Victims of the Conflict10 reached between the Colombian Government and the rebel Fuerzas Armadas Revolucionarias de (p. 361) Colombia—Ejército del Pueblo (usually referred to as ‘FARC’) makes provision for a new ‘Special Jurisdiction for Peace’ to consist of a Peace Tribunal and Judicial Panels to determine which cases of grave violations of human rights and IHL committed in the Colombian Civil War can go to trial, the sanctions provided for have likewise been criticized for ‘not reflect[ing] accepted standards of appropriate punishment for grave violations and mak[ing] it virtually impossible that Colombia will meet its binding obligations under international law to ensure accountability for crimes against humanity and war crimes’.11

  • •  As a mandated outcome of the 31st International Conference of the Red Cross and Red Crescent in 2012, the International Committee of the Red Cross (ICRC) and the Swiss Government initiated a consultation process with states in order to identify and propose possible ways of strengthening legal protection for victims of armed conflicts by ‘exploring ways of enhancing and ensuring the effectiveness of mechanisms of compliance’ with IHL.12 In particular, it was proposed to institute a regular Meeting of States, which would serve primarily as a non-politicized forum for states ‘to examine IHL issues of common concern based on dialogue and cooperation’ and to carry out activities (such as the sharing of best practices and technical expertise, to be agreed by participating states) related to the implementation of IHL, in order to strengthen respect for the law.13 The proposed mechanism, therefore, was conceived as something entirely non-partisan and unthreatening to states’ sovereignty. Nevertheless, after four consultative meetings convened by Switzerland and the ICRC with the participation of a total of ninety-one states, it proved impossible to reach a multilateral agreement on even this relatively harmless proposal;14 instead, all that could be agreed upon was to launch a four-year inter-governmental process to discuss further the methods of enhancing the implementation of IHL, with a view to reporting back to the next Conference.15

This chapter takes a holistic view of the implementation of IHL as including all the various tools which may be used to render IHL effective in practice, whether they are used primarily before a situation of armed conflict arises, or during or after such a situation, whether they invoke the civil responsibility of the state or the criminal responsibility of individuals, and whether they fall to be implemented in a national or international (p. 362) context. Enforcement of IHL, though arguably susceptible of treatment as a separate topic discrete from implementation as such, is here subsumed within the same framework as it is a logical and necessary consequence of IHL implementation. Starting with a brief review of the evolution and development of national and international implementation mechanisms for the laws of war during the era of modern warfare from the early seventeenth century to the aftermath of the Second World War, the chapter sets out the contemporary legal framework provided by treaty instruments and recognized as customary international law before examining specific state obligations relating to pre-conflict preventive measures, the supervision of conduct and repression of violations during conflict, and the subsequent enforcement of IHL by judicial, quasi-judicial, and non-judicial means. Finally, the chapter considers the increasingly important role played by non-state actors (NSAs), such as NGOs, civil society, and the media, in monitoring and advocacy on IHL issues.

2.  The Historical Context

Early attempts at the enforcement of the laws of war appeared through the prism of punishing those who were judged guilty of violating that body of rules. Although the notion of having rules of law in war (jus in bello) is probably about as old as organized warfare itself, and concepts of honour and chivalry in ancient and mediaeval warfare were historically adjudicated in various forums,16 it was not until the advent of mass citizen-armies organized by nation-states as a public activity in the course of the seventeenth century that something resembling systematic national implementation of the laws of war began to take place. Even then, these were couched in terms of domestic military law and the extension of national criminal offences to cover military discipline, rather than international law as such; among the earliest known examples are the Articles of War promulgated for the Swedish army in the Thirty Years’ War (1618–1648).17 In England the source of disciplinary enforcement for the Army was the royal prerogative, under which King Charles I promulgated ‘Lawes and Articles of Warre’ (building on ad hoc mediaeval precedents dating back to Plantagenet times) in 1625—these were reissued in 1629 and 1639;18 their substantive essence, along with the constitutional authority to issue them, began to be transferred to a statutory footing with the adoption of the first Mutiny Act in 1689. Discipline in the Royal Navy was covered by statute for the first time shortly after the Restoration of King Charles II.19 These early articles of national military law provided, naturally, for the trial and punishment of soldiers and sailors accused of breaches of service discipline; but they also enacted a variety of offences amounting to crimes under the civil law, which under modern (p. 363) IHL could be characterized as war crimes or crimes against humanity. Nevertheless, the actual effectiveness of such purely national and disciplinary codes for the protection of the civilian population—in later times to become one of the main aspects of IHL—in the early modern period of warfare has been questioned.20

While the jurisdiction of a State to conduct trials of its own soldiers for violations of national service law has never been disputed, as it is an obvious aspect of criminal jurisdiction over a states’ own nationals, it is not clear exactly when it became definitively accepted that a state could legitimately assert such enforcement jurisdiction in respect of enemy soldiers (ie foreign nationals) who, after capture, were accused of violating the laws and customs of war. Early modern writers on international law suggested that persons who violated the laws of war, by analogy with pirates, were to be considered mere banditti or brigands, and could be subjected to punishment by whichever authority’s hands they fell into.21 The main examples in early modern practice derive largely from the US—the first systematic institutional mechanism for punishing what would today be called war crimes appeared in the Mexican–American War (1846–1848), when Major General Winfield Scott’s General Orders No 20 instituted military commissions for the trial and punishment of ‘atrocious crimes’ whether committed by civilians or military persons, Mexicans or Americans, namely: ‘[m]urder, premeditated murder, injuries or mutilation, rape, assaults and malicious beatings; robbery, larceny, desecration of Churches, cemeteries or houses, and religious buildings; and the destruction of public or private property that was not ordered by a superior officer’.22 The first clear enunciation of the notion of prosecuting enemy soldiers for ‘violation of the laws of war’ appears in the orders issued at the behest of the US Army’s department commander in Missouri, Major General Henry Halleck, in respect of guerrilla warfare against irregular Confederate forces during the American Civil War (1861–1865):

… a soldier duly enrolled and authorized to act in a military capacity in the enemy’s service is not according to the code military individually responsible for the taking of human life in battle, siege, &c., while at the same time he is held individually responsible for any act which he may commit in violation of the laws of war. Thus he cannot be punished by a military tribunal for committing acts of hostility which are authorized by the laws of war but if he has committed murder, robbery, theft, arson, &c., the fact of his being a prisoner of war does not exempt him from trial by a military tribunal.23

This power to enforce the laws of war by prosecuting one’s own or the enemy’s soldiers for violations was clearly generally acknowledged by the late nineteenth century,24 and was to (p. 364) be reasserted as a result of the wholesale atrocities committed during both World Wars.25 As noted by authorities at the time, however, it was not always possible for a belligerent to secure custody of an accused in order to bring him to trial; and if the state of his nationality refused or otherwise failed to investigate and prosecute him,26 a standard recourse for the injured state was to have resort to the right of belligerent reprisal, whereby a belligerent would engage temporarily in proportionate illegal conduct with a view to inducing the enemy to desist from his own unlawful behaviour.27

Aside from enforcement by means of criminal sanctions, the concept of specifically implementing parts of the laws of war by the enactment of regulations and legislation appears to have entered the lexicon of international conventions only with the adoption of the first Geneva Convention in 1864; initially this was conceived of as being a matter which was delegated to military commanders in the field, who would act in accordance with the instructions promulgated by their governments.28 Subsequent iterations of the Geneva Convention in the early twentieth century repeated that injunction and also required signatories to ‘take the necessary steps to acquaint their troops … with the provisions of this convention and to make them known to the people at large’29 and also to introduce ‘such measures as may be necessary’ to prevent the unauthorized use of the protected emblem of the Red Cross and to repress ‘individual acts of robbery and ill treatment of the sick and wounded of the armies, as well as to punish … the wrongful use of the flag and brassard of the Red Cross’.30 These requirements pointed the way forward to the post-1945 emphasis on enactment of penal sanctions in domestic legislation and on dissemination of the Geneva Conventions, as discussed further in section 4 ‘The Geneva Conventions and Their Additional Protocols’ below.

On a more general level, in the pre-1945 era, the only other specific provision for giving effect to the laws of war was to be found in the Hague Convention’s adoption of the general rule of state responsibility for unlawful acts by state organs: ‘A belligerent party which violates the provisions of the [annexed] Regulations shall, if the case demands, be liable to pay compensation. It shall be responsible for all acts committed by persons forming part of its armed forces.’31 This, however, was and is a general doctrine of public international (p. 365) law and is in no way peculiar to the laws of war; neither can it be said to constitute a rule of enforcement per se, perhaps even less so a rule for specific implementation of the law. Although it was used against Germany by the victorious Allied Powers in the infamous reparations clauses of the peace settlement after the First World War,32 in historical terms and notwithstanding the settled rules of international law this represented something of an aberration: in the aftermath of the Second World War the emphasis returned very firmly to criminal sanctions and the prosecution of accused war criminals.33 Both Germany and Japan as occupied territories after 1945 saw the creation of military tribunals—the Nuremberg and Tokyo Trials, respectively, for the trial of major war criminals, and a myriad of national tribunals, in both the occupied states and their erstwhile enemies, for the trial of so-called minor war criminals. But these were ad hoc expedients adopted by the victors exclusively against their defeated enemies in a situation of debellatio; systemic reliance upon mechanisms of national implementation of IHL would not come until the adoption of the updated Geneva Conventions in 1949.

3.  The Contemporary Framework

A.  Generalities

Broadly speaking, the contemporary implementation of IHL in the holistic sense alluded to in the introduction to this chapter may be achieved in some seven different ways.34 It is difficult to gauge the relative impact and effectiveness of these methods, as they are quite different from each other: some consist of implementation stricto sensu, others are more in the nature of prevention and/or punishment, while yet others are not strictly speaking legal in nature. Nevertheless, for the purposes of summarizing them here, they may be enumerated in approximately the following generalized order of impact and effect:

  1. (1)  belligerent reprisals;

  2. (2)  state responsibility;

  3. (3)  dissemination and instruction;

  4. (4)  command responsibility;

  5. (5)  national implementation;

  6. (6)  criminal prosecution;

  7. (7)  external scrutiny/pressure.

For the purposes of this chapter, these aspects of implementation are considered by reference to a temporal framework: those that exist under general public international law are (p. 366) dealt with first, followed by obligations of prevention that arise before armed conflicts, then securing compliance during armed conflict, then enforcement—which usually, though not invariably, occurs in the aftermath of armed conflict. This is followed by some discussion of non-judicial methods that are nevertheless established by law; methods of scrutiny that are primarily political or diplomatic, or that arise as a result of media or social pressure, are considered last. It should be borne in mind that there is some inevitable overlap between some of the methods to be considered, such that neither the categorization nor the methodology of their analysis is perfect.

The implementation of IHL treaties since the end of the Second World War has become relatively systematized and has tended to follow a set pattern, depending on the type of treaty in question, all under the chapeau of the general doctrine of state responsibility in public international law, as noted in section 2 ‘The Historical Context’ above. The 1949 Geneva Conventions and their 1977/2005 Additional Protocols have specific inbuilt mechanisms for their own dissemination, implementation, and enforcement. The majority of the other IHL treaties adopted post-1945 are concerned with the prohibition or restriction of various types of weaponry, which generally fall to be implemented by means of the creation of specific criminal offences in the national laws of states parties to those treaties.

B.  Belligerent Reprisals

Historically, in the absence of international institutions and a rule-of-law-based system of international governance, belligerent reprisals, as a means of self-help, were one of the main ways in which a state could attempt to secure greater compliance with the law by its enemies. Although the theoretical possibility of belligerent reprisals remains in the law today, the likelihood of their being used in contemporary armed conflicts has been increasingly attenuated by the progressive interdiction of whole categories of persons as legitimate targets for reprisal action in successive treaties of modern IHL. Thus, for example, reprisals against the civilian population and the natural environment are both now flatly prohibited.35 The idea of belligerent reprisals is to compel cessation of violations by the adverse party in an armed conflict by resort to a proportionate action that is itself illegal. Unfortunately, they often achieve precisely the opposite effect, producing a downward spiral of retaliation and counter-retaliation which undermines the law rather than enhances it, as seen in incidents of reciprocal shackling of prisoners of war (POWs) by the UK, Canada, and Germany during the Second World War, ostensibly in reaction to attempts by POWs to escape from captivity and subsequent ‘mutinies’ in POW camps.36 Generally, the use of belligerent reprisals in the twenty-first century—if it is even seriously contemplated—will in many countries be circumscribed by stringent conditions and subject to political approval at the highest level of government.37

(p. 367) C.  State Responsibility

In the modern era states have continued to present civil claims for monetary or other satisfaction against each other, based on allegations that IHL was violated by members of the regular state armed forces; that is, by individuals or units belonging to an organ of the state.38 Such claims generally involve an element of international arbitration in order to be adjudicated. Following the conclusion of the Gulf War, a United Nations Claims Commission (UNCC) was established as a subsidiary organ of the Security Council in order to process claims for compensation in respect of losses and damage resulting directly from the Iraqi occupation of Kuwait in 1990–1991,39 To date the UNCC has paid out some $47.8 billion in compensation awards, with about $4.6 billion (awarded for production and sales losses resulting from the destruction of Kuwaiti oil fields) still outstanding.40 The Algiers Peace Agreement, which terminated the 1998–2000 armed conflict between Ethiopia and Eritrea, created a Claims Commission under the auspices of the Permanent Court of Arbitration to adjudicate:

all claims for loss, damage or injury by one Government against the other, and by nationals … of one party against the Government of the other party or entities owned or controlled by the other party that are (a) related to the conflict … and (b) result from violations of international humanitarian law …41

Sitting between 2004 and 2009, the Eritrea–Ethiopia Claims Commission delivered a total of seventeen Awards, of which all but three relate to alleged violations of IHL, in response to eight claims submitted by Ethiopia and thirty-two submitted by Eritrea.42

Similarly, the United Nations (and other international or regional organizations, if appropriate) may consider the attribution of responsibility for damage and loss suffered by the organization itself and its employees in the course of military operations, as was done for instance in respect of incidents of such damage and loss suffered by various UN specialized agencies during the 2008–2009 conflict between Israel and Hamas in the Gaza Strip.43 On that occasion damage worth in excess of $11 million was attributed to actions by the Israel (p. 368) Defence Forces, with a provisional estimate of some $29,000 worth of damage being laid at the door of a Palestinian armed faction, most likely to have been Hamas.44

4.  The Geneva Conventions and Their Additional Protocols

It is appropriate to deal with the generalities of the 1949 Geneva Conventions and the 1977 Additional Protocols thereto separately within the framework of the contemporary law, as they have their own particular implementation scheme. The Conventions’ starting point is that, ‘The High Contracting Parties undertake to respect and to ensure respect for the present Convention[s] in all circumstances’, an injunction which is repeated verbatim in the first Protocol (but not the second).45 It is therefore immediately apparent that there are certain provisions which fall to be implemented during peacetime as well as in situations of armed conflict—these will be discussed in section D ‘Non-Judicial Mechanisms of Implementation’ below.

Insofar as implementation during situations of armed conflict is concerned, the practice prior to 1949 had generally been to make a state’s application of its treaty obligations dependent on reciprocity and to include them among the final provisions of each treaty, as expressed in the following typical formulation: ‘The provisions of the present Convention do not apply except between contracting Powers, and then only if all the belligerents are parties to the Convention.’46 Although this approach persisted in the interwar period’s sole adopted treaty regulating the conduct of hostilities,47 the updated Geneva Conventions adopted in 1929 introduced the ‘in all circumstances’ rule and modified for the first time the ‘all-participation clause’ by stipulating that, ‘if one of the belligerents is not a party to the Convention, its provisions shall, nevertheless, remain binding as between the belligerents who are parties thereto’.48 This new wording did not alter the technical possibility that the Conventions would remain legally inapplicable in cases where one belligerent was, but its opponent was not, a party to the Conventions; nevertheless, the introduction of the ‘in all circumstances’ language created a potentially inconsistent obligation. The effect could be seen in Germany’s refusal to apply the Geneva Conventions on the Eastern Front during the (p. 369) Second World War on the basis that the Soviet Union was not a party to those instruments, although those deemed responsible for the resulting ill-treatment of Soviet prisoners of war were subsequently condemned as war criminals.49

There has been a shift in emphasis since the Second World War away from all-participation clauses to a more universalist approach, as well as placing these provisions at the very start of the substantive contents of the modern instruments, rather than burying them among procedural provisions at the end of the documents. These can be attributed to a desire to strengthen the imperative encapsulated by the maxim pacta sunt servanda: the inclusion of the phrase ‘in all circumstances’ stresses that the treaties are to be applied even outside the parameters of the situations to which they pertain—namely, armed conflicts—by taking in peacetime the preventive actions, to be discussed in 4.A ‘Pre-Conflict: Obligations of Prevention’ below. Notwithstanding the importance attached to the treaty texts, it is worth recalling that the International Court of Justice (ICJ) has stated that, ‘[the obligation in Common Article 1] does not derive only from the Conventions themselves, but from the general principles of humanitarian law to which the Conventions merely give specific expression’.50

Given the vagueness of the wording in Common Article 1, the question may well be asked: vis-à-vis from whom a state is to ‘ensure respect’. Obviously it must ensure respect by its own regular armed forces, and also by irregular forces whose conduct is attributable to it.51 Ensuring respect by other states, in the sense of influencing them in the context of general friendly relations, or pursuant to a specific alliance, or at the ‘hard end’ of joint military operations in a multinational coalition, wherein different nations may not necessarily all be parties to the same IHL treaties, can be surprisingly problematic.52 Differences between allied nations in respect of legal obligations, or even of bona fide interpretation of legal provisions—as in, for example, detailed aspects of the definition of military objectives under article 52(2) of API—do not give rise to any doctrinal controversy in this respect. More difficult, however, are situations where individual states may reasonably be expected to use their influence on friends and allies to induce the latter to comply with IHL in the conduct of their military operations. Diplomatic and economic policies may eclipse humanitarian concerns, as attested by the British Government’s 2016 response to criticism in respect of its arms sales to Saudi Arabia in light of the latter’s extremely destructive campaign in Yemen.53 Occasionally a multilateral attempt is made pursuant to a treaty,54 (p. 370) or within the forum of an international organization to exert pressure upon a perceived delinquent state in order to induce it to comply with its obligations under IHL.55 However, this often seems to achieve little other than to push the target state into a defensive and uncooperative position of reflexive denial.56 Arguably the most credible attempts to ‘ensure respect’ for IHL on the part of other states are evinced by international court decisions,57 and diplomatic responses thereto,58 but such cases are rare indeed. As for the notion that a state should ensure respect for IHL on the part of NSAs, this will plainly be a dead letter insofar as opposition NSAs on the state’s own territory are concerned, but it would be a reasonable expectation that a state should prevail upon NSAs over which it has effective control, whether within its own borders or elsewhere, to conduct their operations in accordance with IHL.59

A.  Pre-Conflict: Obligations of Prevention

Although the most publicly visible form of IHL implementation is post-conflict enforcement by means of criminal proceedings for the punishment of violations, and it is through that prism that the consciousness of IHL has largely become embedded in the general population in many countries, actually modern IHL mandates various measures to be taken by states in advance of any armed conflict breaking out with a view to avoiding or minimizing the risk of future violations. Broadly, these may be broken down into those measures that are of a general, ongoing nature and those that entail specific one-off actions. While compliance with these obligations of prevention is not, in and of itself, a panacea for IHL violations, and they are only addressed to states as opposed to NSAs, it is arguably the case that effective implementation of these measures assists in the development of a culture of compliance with the law, as well as mitigating the opportunities for future violations.

(p. 371) 1.  General measures

Each of the 1949 Geneva Conventions contains a whole chapter or part headed ‘Execution of the Convention’.60 This is equally the case for API,61 though not for APII, whose sole provision for implementation is the requirement that, ‘This Protocol shall be disseminated as widely as possible.’62 The central requirement is a dual one, of dissemination and instruction: states undertake to propagate the text of the Conventions ‘as widely as possible in their respective countries’ so that ‘the entire population’ may become aware of their principles.63 This is to be achieved by educating the civilian population at large, as well as the members of armed forces, in the principles and rules of IHL. As to the civilian population, the subject may be included in the curriculum of universities and even (in some countries) schools, and there is a myriad of programmes such as moot court competitions, simulations, subject-specific projects, and voluntary youth instruction, all designed to foster an interest in and awareness of IHL.64 Inevitably, however, this method of implementation is somewhat uneven, depending as it does on the availability of staff expertise and educational resources: even in a country like the UK, for example, IHL as a discrete subject is comprehensively taught at little more than a handful out of approximately 100 university-level law schools, and there is no evidence of any government initiatives to promote the dissemination of IHL among the general population in the UK, although the British Red Cross does encourage the teaching of aspects of IHL in schools.65

A crucial part of the dissemination of IHL is the education and training of armed forces, which is expressly mandated by the provisions discussed above. This is primarily the responsibility of the military legal advisory services, which now exist in virtually all states around the world: for example, in the British Army, such instruction is delivered via the medium of the Mandatory Annual Training Tests (MATTs), which must be taken by all active and reserve soldiers; currently MATT 7 is designated as covering Operational Law, including the Law of Armed Conflict. Specific pre-operational deployment training in IHL is provided by officers of the Army Legal Services (ALS) Operational Law Branch, based in the Land Warfare Centre at Warminster. For officers, pre-commission instruction in IHL is provided by the Department of Defence and International Affairs at the Royal Military Academy Sandhurst, and opportunities exist for subsequent academic study to Masters (p. 372) and Doctoral level at various higher education institutions. IHL is expressly included on the staff courses of many states’ staff colleges, such as the Joint Services Combined Staff College at the UK Defence Academy, the Italian Centre for Defence Higher Studies, and the Sri Lankan Defence Services Command and Staff College. Similar programmes of legal instruction, which may or may not include university-level programmes of study, exist in armed forces as diverse as those of Uruguay, Algeria, and Indonesia: the pattern is now genuinely quite universal.

A further layer of education in IHL for armed forces is provided by API, which requires states to maintain an establishment of legal officers, ‘to advise military commanders at the appropriate level … on the appropriate instruction to be given to the armed forces on this subject’.66 In some states, such as Canada or the Republic of Ireland, military legal advisers are tri-service; in others, such as the US and the UK, the various services that make up the armed forces maintain their own completely separate legal advisory services.67 While these military legal services provide education and training in IHL for the rest of the armed forces, they also themselves often receive such training from academic providers; for example, in the UK, ALS officers currently attend academic courses in international law (including IHL) at the University of Nottingham, while Royal Navy lawyers attend the University of Oxford; Royal Air Force Legal Officers have in recent years attended academic courses provided by the University of Bristol and by Cranfield University at the UK Defence Academy. On an international level, remarkable work in IHL education for military officers (both lawyers and operators) has for many years been done by the International Institute of Humanitarian Law at San Remo (Italy),68 as well as on a more geo-politically restricted basis by such institutions as the NATO School at Oberammergau (Germany),69 and the Asia Pacific Centre for Military Law (Australia).70 Operationally, military legal advisers fulfil a critical role by advising the commanders to whose staff they are attached about a wide range of legal issues, including the application of IHL in—for instance—the selection of targets for attack and the precautions to be observed in planning and executing such attacks, and the classification and treatment of battlefield detainees.71

Although the mandating of legal advisers for armed forces in international treaty law since 1977 has given added impetus to the production and status of modern military law manuals, the precedents for such documents, as outlined in section 2 ‘The Historical Context’ above, go back several centuries.72 Such manuals fulfil a number of functions, all of them equally important in the legal regulatory framework of state armed forces.73 They may (p. 373) provide evidence of states’ views as to the scope, ambit, and interpretation of rules of IHL, and the normative status thereof in customary international law.74 Ultimately their most practical purpose in terms of the implementation of IHL is that they tell soldiers what the law is and according to what legal standard their actions in armed conflict will be judged.75 Such manuals may be published exclusively in official format,76 or they may be made separately available as an academic publication.77 One innovative approach is to publish them with extensive academic commentary.78 However precisely they are publicized, these military manuals—and the Rules of Engagement that are based on them—are a crucial aspect of the dissemination of IHL to armed forces.

2.  Specific measures

Various treaties that make up the corpus of codified IHL impose requirements for state parties to undertake specific measures of implementation: principally, these are the requirements in the Geneva Conventions and API (along with many of the weaponry treaties) to enact certain criminal offences into states’ national legal systems with a view to securing compulsory enforcement jurisdiction, and the promulgation of protective measures in respect of particular objects, areas or persons. While these measures may be taken at any time, it is obviously best, with an eye to the prevention of violations, for them to be taken at an early stage before any armed conflict breaks out.

The mandatory repression of grave breaches of the Geneva Conventions and of API requires states ‘to enact any legislation necessary to provide effective penal sanctions’ for their commission,79 a jurisdiction which is then enforced according to the principle of aut dedere aut judicare—whereby states are under a legal obligation to search for alleged perpetrators and either place them on trial in their own courts or extradite them to any other state that wishes to do so.80 In the large majority of states the implementation of this obligation has necessarily entailed the passage of special legislation creating new criminal offences and providing for extradition arrangements, as exemplified by the UK’s Geneva Conventions (p. 374) Act 1957 and Geneva Conventions (Amendment) Act 1995.81 This process was given added impetus for many states in the years following the entry into force of the 1998 Rome Statute of the International Criminal Court, because of the need to implement the principle of complementarity of jurisdiction contained therein.82 In addition to the punishment of grave breaches as war crimes, there is also specific provision for the penal repression by special legislation of any abuse of the various distinctive emblems of the Red Cross.83 Various other IHL treaties, notably those that prohibit the use of specified types of weaponry, similarly contain obligations to criminalize in national law the conduct that is prohibited by treaty.84

Perhaps less obvious than the measures relating to penal repression by the creation of criminal offences in national law are various treaty provisions requiring specific practical actions by state authorities. These are generally of an unspectacular, often technical, nature: for example, there is an obligation ‘to prepare in time of peace for the safeguarding of cultural property situated within their own territory against the foreseeable effects of an armed conflict, by taking such measures as [the High Contracting Parties] consider appropriate’.85 States may conclude agreements as to the designation of demilitarized zones, with the aim of protecting an area and its civilian population against military operations,86 although the ICRC has conceded somewhat enigmatically that, ‘it is unlikely that two or more States will agree in advance to keep one or more zones clear of military operations in the event of a conflict breaking out between them: this seems, at least, a rather theoretical point’.87 Although the rationale for the existence of the possibility in peacetime is thus not very clear, nevertheless it exists on the face of the law.

As military history has amply demonstrated, particularly since the Industrial Revolution, one of the most significant peacetime activities by states to have a direct bearing on armed conflict is the development of new weaponry. In light of the rules of IHL prohibiting the employment of weapons that are indiscriminate or that cause superfluous injury and unnecessary suffering, a precautionary requirement was introduced into the law in 1977:

In the study, development, acquisition or adoption of a new weapon, means or method of warfare, a High Contracting Party is under an obligation to determine whether its (p. 375) employment would, in some or all circumstances, be prohibited by [API] or by any other rule of international law applicable …88

While the precise methodologies, as well as the detailed substance, of these weapons reviews are classified by the states concerned for inevitable reasons of national security—and only a handful of High Contracting Parties to the Protocol are known to conduct them at all—an important recent move to greater openness in this context is the institution in 2015 of an annual Weapons Review Forum, convened on behalf of the UK MoD by the Development, Concepts and Doctrine Centre (DCDC) in the UK Defence Academy at Shrivenham. This initiative brought together state representatives, defence industry and procurement teams, academics, the ICRC and other NGOs to compare their practices and learn from each other’s experiences.89

B.  Compliance during Armed Conflict

It is hardly necessary to state that the ideal position to attain is one of full compliance with the rules of IHL during actual situations of armed conflict, since those are the situations in which IHL applies. It is a tragedy for the law and perceptions thereof that in contemporary armed conflicts such compliance is usually conspicuous by its absence. All too often, insurgent NSAs that display scant respect for the law, and indeed have little incentive to comply with it, are pitted against state armed forces that persist in regarding the former as ‘terrorists’ and show correspondingly little inclination to give them the benefit of the law. Arguably there has not been a generally ‘clean’ armed conflict, in which both sides were scrupulous in their adherence as far as circumstances permitted to the letter and spirit of the law and where there were very few (if any) accusations of war crimes, since the Falklands War between Argentina and the UK in 1982. However, the picture is not irredeemably gloomy: for a variety of reasons, NSAs can and do engage with IHL, and accept and apply its principles.90 Although it has never been used successfully, a mechanism exists in API whereby, as a consequence of the extended definition of international armed conflicts to include those ‘in which peoples are fighting against colonial domination and against racist régimes in the exercise of their right of self-determination’,91 an authority representing such a people may make a unilateral declaration undertaking to apply the Geneva Conventions and the Protocol.92 In reality, such putative declarations have been stymied by the relevant states’ obfuscations due precisely to their unwillingness to accept the extended scope of application of API.93 (p. 376) This notwithstanding, it is possible for NSAs to signal their willingness to comply with IHL by both unilateral actions—such as accepting engagement with the ICRC, issuing internal codes of conduct and enforcing discipline,94 making Deeds of Commitment,95 and entering into special bilateral or multilateral agreements such as Memoranda of Understanding.96

Within regular organized armed forces, the principal mechanisms for securing compliance with IHL are the enforcement of military discipline and the doctrine of command responsibility. Armed forces are required to be subject to ‘an internal disciplinary system which, inter alia, shall enforce compliance with the rules of international law applicable in armed conflict’.97 This in turn relies on the commander’s discharge of his responsibility to supervise his subordinates. Although command responsibility as a modern legal doctrine was created in less than ideal circumstances, and applied in a way that would surely be thrown out of court instantly today,98 it is now mandated by IHL in the form of the requirement that commanders take all feasible measures to prevent or repress violations of the law committed by troops under their command, provided that they know or have information which should enable them to conclude in the circumstances at the time that such violations are being committed or going to be committed.99 This is a form of liability based on omission, rather than commission; it is self-evident that a commander who actually orders his troops to commit a violation will be guilty as a principal of that crime. The Protocol places commanders under a positive duty to ensure that troops under their command are aware of their obligations under IHL, to prevent and suppress violations of the law by those troops, and to report such violations to the authorities and initiate disciplinary or penal action as required.100 Although the language of the Protocol is couched exclusively in terms of military commanders, the latest form of the doctrine as enshrined in the 1998 Rome Statute of the International Criminal Court extends the concept to ‘a person effectively acting as a military commander’ and to persons not in traditional military-type superior–subordinate relationships, but where the superior has ‘effective authority and control’ over the subordinate.101

(p. 377) C.  Post-Conflict Enforcement: Criminal Justice Mechanisms

The modern consciousness of IHL and its effective implementation has been developed through the prism of criminal justice: essentially this has meant the prosecution of persons alleged to have committed violations of the law in armed conflicts, as an outgrowth of the disciplinary powers of the commander discussed above. Until the advent of truly international criminal tribunals in the twentieth century, this justice was always dispensed by national criminal courts, which retained a nationality-based jurisdiction to prosecute soldiers of their own side who were accused of violating the laws of war,102 and simultaneously asserted what came to be recognized as a universal jurisdiction likewise to prosecute soldiers of the adverse party after capture.103 The nationality-based jurisdiction over own soldiers—the notion that military troops in effect carry the criminal law of their own country with them, wherever in the world they are deployed—remains an integral part of military law in all states to this day,104 and has given rise to some of the most famous war crimes prosecutions of modern times, like those of Lieutenant William Calley for the massacre of civilians at My Lai during the Vietnam War,105 and Sergeant Alexander Blackman for the murder of a wounded Taliban insurgent in Afghanistan.106

Putting aside the International Military Tribunals convened by the Allied Powers’ occupation authorities in Germany and Japan after the Second World War, the first genuinely international tribunals for the prosecution of serious violations of IHL were established by the UN Security Council pursuant to its Chapter VII powers in the early 1990s.107 They have since been followed by other ad hoc international or ‘internationalized’ tribunals,108 generally established by special treaty agreements between the UN and the individual states concerned, but the most important progress was made by the adoption of the Rome Statute of the International Criminal Court (‘ICC’) in 1998. The ICC has been in existence since 2002 and has heard such pioneering cases in the enforcement of IHL as those involving the recruitment and use of child soldiers109 and directing attacks against cultural property during armed conflict.110 In addition, the Statute’s articles providing for ICC jurisdiction over war crimes and crimes against humanity may to a considerable extent be viewed as a de facto codification of those crimes for the modern era. Although the primary jurisdiction to punish war crimes remains that of individual states according to their national legislation, (p. 378) the importance of having a permanent international court to punish the most serious violations of IHL can hardly be overstated in terms of the law’s enforcement.

D.  Non-Judicial Mechanisms of Implementation

Finally, a variety of mechanisms that do not involve judicial investigations, prosecutions, or other legal sanctions fall to be considered under this generic heading. Although they are mostly quite different from one another, they have in common that they generally seek to obtain compliance with IHL by the exertion of external pressure and public scrutiny, as well as unofficial monitoring and advocacy of issues related to violations of the law in armed conflicts. For the purposes of discussion in this context, it is expedient broadly to divide them into two types: those that are mandated by IHL itself, and those that are not.

1.  Mechanisms mandated by IHL

The four Geneva Conventions and API all contain provisions for the designation of Protecting Powers to represent belligerent states’ interests vis-à-vis their adverse parties in situations of international armed conflict.111 By this system, neutral states voluntarily undertake to safeguard the supervision and implementation of IHL as between belligerents, who have no direct formal mutual diplomatic relations due to the existence of a state of armed conflict between them. This is not to be confused with the more generic diplomatic protection of interests, whose protagonists are also often referred to as Protecting (or Protective) Powers, but whose operation is not confined to situations of armed conflict.112 The system under IHL had its genesis in the late nineteenth century—it has been traced in its modern form specifically to the Franco-Prussian War (1870–1871), when the US Minister in Paris arranged the evacuation of citizens of the North German Confederation from French territory—and was entirely a creature of customary law until its incorporation into the codified framework of the Geneva Conventions.113 Protecting Powers can fulfil a valuable role in securing the protection of POWs by visiting camps and monitoring trials of POWs and civilians of the adverse party and in making representations to the relevant belligerent concerning general compliance with IHL. Unfortunately, the system of Protecting Powers has largely fallen into disuse in modern armed conflicts, principally because the designation of a Protecting Power must be agreed by the adverse party. In most recent armed conflicts such mutual agreement has not often been forthcoming, since it has been difficult to find a neutral state maintaining equally good diplomatic relations with both parties to the conflict. The Falklands War (1982) was the last in which neither side objected to the other’s nominee.114

Although one practical response to the decreasing use of Protecting Powers has been to have recourse to the good offices of the ICRC, actually the role of the ICRC in securing (p. 379) compliance with IHL is clearly mandated in the law that has evolved since the first Geneva Convention in 1864. The ICRC has the right under treaty law to offer its impartial services in place of a Protecting Power, if none is designated,115 and to visit and interview POWs,116 and other protected persons,117 as well as assisting in the institution and recognition of hospital and safety zones,118 and various other specific humanitarian tasks on the battlefield. The organization also communicates regularly with the parties to armed conflicts with its observations and concerns as to their compliance—or lack thereof—with IHL; normally these communications are not published, in order to preserve the confidence of the belligerents as to the ICRC’s neutrality and impartiality and discreetly to encourage compliance with IHL rather than pointing an accusatory finger, but on some rare occasions the organization has famously been moved to go public with its criticisms.119 The ICRC Advisory Service on IHL, made up of expert legal advisers, assists states with the national implementation of IHL; through its network of Regional and National Delegations and delegates to armed forces and non-state armed groups (NSAGs), the organization maintains a strong global presence and is indefatigable in its advocacy of respect for IHL.

A further mechanism for monitoring compliance is available in the form of the International Humanitarian Fact-Finding Commission (‘IHFFC’). This body was created in 1977,120 and became operational in 1992, with a mandate impartially to investigate alleged violations of IHL and confidentially establish facts in cases of mutual allegations and denials of responsibility.121 With seventy-six states having accepted its competence in accordance with the Protocol—although the Russian Federation notably withdrew its acceptance in 2019—in theory the IHFFC should be a prime tool for the enforcement of the law, except for the fact that the consent of both belligerent states or other parties to the conflict is required; it also has no powers of enforcement, but can simply issue confidential reports. To date the Commission has been used only once, to lead an independent forensic investigation in Luhansk province in Eastern Ukraine in 2017—a remarkable testimony to the reluctance of states, commented upon in the Introduction to this chapter, to submit their military actions to any kind of impartial authoritative scrutiny.

5.  Conclusion: Other Mechanisms

In a world of twenty-four-hour rolling international news coverage, it is inevitable that situations of armed conflict should attract a great deal of attention from the media. The phenomenon often referred to as ‘the CNN effect’, while decidedly modern in terminology, arguably dates back in its earliest form to the horrified public fascination stimulated by photographs taken in the aftermath of the fighting on the great battlefields of the American (p. 380) Civil War (1861–1865).122 Today, images of the atrocities of war are beamed into the living rooms and onto the smartphones of millions around the world on an almost daily basis. Users of social media are quick to vent their fury in apparently spontaneous reaction to missile strikes that have the effect, whether desired by the attacker or not, of harming the civilian population. In this kind of febrile environment it is not surprising that a multiplicity of non-governmental and civil society organizations thrive on bringing external scrutiny and pressure to bear on governments to account for the conduct of their armed forces in conflict: Amnesty International, Human Rights Watch, B’Tselem, MSF, and a myriad of other similar organizations serve to monitor violations and demand accountability in accordance with the law. While this advocacy has had the beneficial effect of helping to raise the profile of IHL and its application in armed conflicts, it has perhaps inevitably led to a backlash in some governmental and military quarters, where the term ‘lawfare’ has acquired increasing (and pejorative) currency.123 In a British context especially, it has come to be used to decry the increasing involvement of European human rights organs as a tool for hampering military operations.124 The growing tendency to apply the standards of civilian life to military operations in human rights complaints has also been condemned as the ‘judicialisation of war’.125

The growing significance of interpretations of IHL by human rights bodies is also evidenced by the increasing tendency of such organs as the UN Human Rights Council to mandate commissions of inquiry, fact-finding missions, and other such bodies to report on situations where violations are alleged to have occurred.126 Although these reports again have the effect of bringing discussions of IHL more into the public domain, the atmosphere is often openly inquisitorial, with the investigated state tending to withhold or restrict co-operation, resulting in an often blatantly one-sided report. Sometimes the mandate, too, is criticized for being one-sided in its focus on violations by state armed forces as opposed to NSAs. Discussion of such reports is all too often excessively politicized, with no discernible achievement other than to foreclose rational and balanced discussion of the substantive issues of IHL.


United Nations Human Rights Council (UNHRC), ‘Situation of Human Rights in Yemen: Report of the United Nations High Commissioner for Human Rights’ UN Doc A/HRC/30/31 (7 September 2015) para 91.

UNHRC, ‘Draft Resolution: Situation of Human Rights in Yemen’ UN Doc A/HRC/30/L.4/Rev.1 (30 September 2015) para 13.

Human Rights Watch (HRW), ‘UN: Rights Council Fails Yemeni Civilians’, Human Rights Watch (2 October 2015) www.hrw.org/news/2015/10/02/un-rights-council-fails-yemeni-civilians.

HRC Resolution 30/18 UN Doc A/HRC/RES/30/18 (12 October 2015).

Report of the Group of Eminent International and Regional Experts as submitted to the United Nations High Commissioner for Human Rights, UN Doc A/HRC/42/17 (9 August 2019).

US Senate Committee on Armed Services, ‘Hearing to Receive Testimony on the Situation in Afghanistan’, Statement of General John F Campbell, Stenographic Transcript (6 October 2015) 14 www.armed-services.senate.gov/imo/media/doc/15-76%20-%2010-6-15.pdf.

Brigadier General Wilson Shoffner, quote in ‘Department of Defense Press Briefing by General Campbell via Teleconference from Afghanistan’, News Transcript, US Department of Defense (25 November 2015) https://www.defense.gov/Newsroom/Transcripts/Transcript/Article/631359/department-of-defense-press-briefing-by-general-campbell-via-teleconference-fro/fro.

‘Letter from HRW to Secretary of Defense Ashton Carter’ (17 December 2015) www.hrw.org/sites/default/files/supporting_resources/hrw_letter_to_sec_def_carter_on_msf_strike.pdf.

See Françoise Bouchet-Saulnier and Jonathan Whittall, ‘An Environment Conducive to Mistakes? Lessons Learnt from the Attack on the Médecins Sans Frontières Hospital in Kunduz, Afghanistan’ (2018) 100 IRRC 337.

10  Acuerdo sobre las Víctimas del Conflicto: ‘Sistema Integral de Verdad, Justicia, Reparación y No Repetición’, incluyendo la Jurisidcción Especial para la Paz; y Compromiso sobre Derechos Humanos (5 December 2015) http://legal.legis.com.co/document/Index?obra=legcol&document=legcol_ee52f558022d4ec8bc714555c034519e (only in Spanish).

11  HRW, ‘Human Rights Watch Analysis of Colombia–FARC Agreement’ (21 December 2015) www.hrw.org/news/2015/12/21/human-rights-watch-analysis-colombia-farc-agreement#_edn1.

12  International Committee of the Red Cross (ICRC), ‘Strengthening Compliance with International Humanitarian Law: Draft Resolution and Concluding Report’, 32nd International Conference of the Red Cross and Red Crescent, 32IC/15/19.2 (Geneva, 8–10 December 2015, 32IC/15/19.2) 7 http://rcrcconference.org/wp-content/uploads/sites/3/2015/10/32IC-DR-and-concluding-report-on-Strengthening-Compliance-with-IHL_EN.pdf.

13  ibid 19.

14  ICRC, ‘No Agreement by States on Mechanism to Strengthen Compliance with Rules of War’ (10 December 2015) www.icrc.org/en/document/no-agreement-states-mechanism-strengthen-compliance-rules-war.

15  ICRC, ‘Resolution 2: Strengthening Compliance with International Humanitarian Law’, 32nd International Conference of the Red Cross and Red Crescent, 32IC/15/R2 (Geneva 8–10 December 2015) http://rcrcconference.org/wp-content/uploads/sites/3/2015/04/32IC-AR-Compliance_EN.pdf. See also Jelena Pejic, ‘Strengthening Compliance with IHL: The ICRC-Swiss Initiative’ (2016) 98 IRRC 315.

16  For a general overview, see Leslie C Green, The Contemporary Law of Armed Conflict (3rd edn, Manchester UP 2008) 26–32; also Robert C Stacey, ‘The Age of Chivalry’, in Michael Howard, George J Andreopoulos, and Mark R Shulman (eds), The Laws of War: Constraints on Warfare in the Western World (Yale UP 1994) 27, 31.

17  See Kenneth Ögren, ‘Humanitarian Law in the Articles of War decreed in 1621 by King Gustavus II Adolphus of Sweden’ (1996) 36 IRRC 438.

18  See Charles M Clode, The Military Forces of the Crown: Their Administration and Government, Vol 1 (John Murray 1869) 18, 429 (annexed Illustration (VI)).

19  Charles II, 1661, ‘An Act for the Establishing [of] Articles and Orders for the Regulating and Better Government of His Majesties Navies Ships of Warr and Forces by Sea’, in John Raithby (ed), Statutes of the Realm: Vol 5, 1628–1680 (first published 1819) 311.

20  See eg Markus Meumann, ‘Civilians, the French Army and Military Justice during the Reign of Louis XIV, circa 1640–1715’, in Erica Charters, Eve Rosenhaft, and Hannah Smith (eds), Civilians and War in Europe, 1618–1815 (Liverpool UP 2014) 100.

21  See eg Emmerich de Vattel, Le Droit des Gens (1758) Liv III, Chap XV para 226.

22  Cuartel General del Egercito, ‘Ordenes Generales—No 20’ (Tampico, 19 February 1847) English translation https://scholarship.rice.edu/jsp/xml/1911/27562/3/aa00208tr.tei.html. For discussion, see John F Witt, Lincoln’s Code: The Laws of War in American History (Free Press 2012) 118–32; Louis Fisher, ‘Military Tribunals: Historical Patterns and Lessons’, US Congressional Research Service Report RL32458 (9 July 2004) 11–14.

23  Department of Missouri, ‘General Orders No 1’ (Saint Louis, 1 January 1862) in US War Department, The War of the Rebellion: A Compilation of the Official Records of the Union and Confederate Armies, Series II, Vol 1 (Government Printing Office 1894) 249.

24  Institute of International Law, Manual of the Laws of War on Land (Oxford 1880) Part III.

25  See James W Garner, ‘Punishment of Offenders against the Laws and Customs of War’ (1920) 14 AJIL 70; Hersch Lauterpacht, ‘The Law of Nations and the Punishment of War Crimes’ (1944) 21 BYBIL 58; Willard B Cowles, ‘Universality of Jurisdiction over War Crimes’ (1945) 33 CLR 177.

26  For centuries it was the custom for commanders on the battlefield to communicate directly with each other under a flag of truce, usually via parlementaires, for a variety of purposes, including bringing each other’s attention to alleged violations of the laws of war: see Green (above n 16) 113–16. As direct governmental control of armed forces increased and technology developed, such communications could be addressed by a commander directly to the enemy government or indirectly between the belligerent governments, via the good offices of a neutral state: see eg correspondence between the British Commander-in-Chief in South Africa and the Afrikaner State Presidents concerning reported abuse of the white flag on the battlefield during the Second Boer War, Telegrams from Field-Marshal Lord Roberts to the Secretary of State for War (Cd 122, 1900).

27  See William Winthrop, Military Law and Precedents (2nd edn, Government Printing Office 1920) 796–9; Shane Darcy, ‘The Evolution of the Law of Belligerent Reprisals’ (2003) 175 Mil L Rev 184.

28  Geneva Convention for the Amelioration of the Condition of the Wounded in Armies in the Field (signed 22 August 1864, entered into force 22 June 1865) 129 CTS 361 article 8.

29  Geneva Convention for the Amelioration of the Condition of the Wounded and Sick in Armies in the Field (adopted 6 July 1906, entered into force 9 August 1907) 202 CTS 144 articles 25–26.

30  ibid articles 27–28.

31  Hague Convention (IV) Respecting the Laws and Customs of War on Land (adopted 18 October 1907, entered into force 26 January 1910) 205 CTS 277 (Hague Convention IV) article 3.

32  Treaty of Peace between the Allied and Associated Powers and Germany (adopted 28 June 1919, entered into force 10 January 1920) 225 CTS 188 (Versailles Treaty) part VIII: Reparation.

33  After World War I the Treaty of Versailles had deferred such matters to German national jurisdiction: see Mahmoud Cherif Bassiouni, ‘World War I: “The War to End All Wars” and the Birth of a Handicapped International Criminal Justice System’ (2002) 30 Denv J Intl L & Pol’y 244, 281–85.

34  For an outline, see David Turns, ‘The Law of Armed Conflict (International Humanitarian Law)’, in Malcolm D Evans (ed), International Law (5th edn, OUP 2018) 840.

35  Protocol Additional to the Geneva Conventions of 12 August 1949, and Relating to the Protection of Victims of International Armed Conflicts (adopted 8 June 1977, entered into force 7 December 1978) 1125 UNTS 3 (API) articles 51(6) and 55(2), respectively.

36  See Jonathan F Vance, ‘Men in Manacles: The Shackling of Prisoners of War, 1942–1943’ (1995) 59 J Mil Hist 483.

37  Eg UK Ministry of Defence (MoD), The Manual of the Law of Armed Conflict (OUP 2004) paras 16.16–16.19.

38  Draft Articles on Responsibility of States for Internationally Wrongful Acts article 4 in Yearbook of the International Law Commission 2001, Vol II UN Doc A/CN.4/SER.A/2001/Add.1 (Part 2) (UN 2001) 30. The generic modern restatement of state responsibility for violations of IHL is contained in API article 91.

39  UN Security Council (UNSC) Resolution 687 UN Doc S/RES/687 (8 April 1991) para 18. Resolution 687 declared, inter alia, that Iraq was ‘liable under international law for any direct loss, damage, including environmental damage and the depletion of natural resources, or injury to foreign Governments, nationals and corporations, as a result of Iraq’s unlawful invasion and occupation of Kuwait’: ibid para16. Note the broad similarity of language and intent between this provision and articles 231–233 of the Versailles Treaty, which affirmed Germany’s liability based on its aggression in 1914 and established a Reparation Commission to consider claims made against Germany in respect of the First World War.

40  For details of the UNCC’s work since 1991, see www.uncc.ch.

41  UNSC, ‘Agreement between the Government of the State of Eritrea and the Government of the Federal Democratic Republic of Ethiopia: Identical letters dated 12 December 2000 from the Permanent Representative of Algeria to the United Nations addressed to the Secretary-General and the President of the Security Council’ UN Doc A/55/686-S/2000/1183 (13 December 2000) annex, article 5(1).

42  For details, see https://pca-cpa.org/en/cases/71/.

43  UNSC, ‘Summary by the Secretary-General of the report of the United Nations Headquarters Board of Inquiry into certain incidents in the Gaza Strip between 27 December 2008 and 19 January 2009’ UN Doc A/63/855-S/2009/250 (15 May 2009).

44  ibid paras 94–95.

45  Geneva Convention (I) for the Amelioration of the Condition of the Wounded and Sick in the Armed Forces in the Field (adopted 12 August 1949, entered into force 21 October 1950) 75 UNTS 31 (GCI); Geneva Convention (II) for the Amelioration of the Condition of the Wounded, Sick and Shipwrecked Members of Armed Forces at Sea (adopted 12 August 1949, entered into force 12 October 1949) 75 UNTS 85 (GCII); Geneva Convention (III) Relative to the Treatment of Prisoners of War (adopted 12 August 1949, entered into force 12 October 1950) 75 UNTS 135 (GCIII); Geneva Convention (IV) Relative to the Protection of Civilian Persons in Time of War (adopted 12 August 1949, entered into force 21 October 1953) 75 UNTS 287 (GCIV); Geneva Conventions Common Article 1 (emphasis added); API article 1.

46  Hague Convention (V) Respecting the Rights and Duties of Neutral Powers and Persons in Case of War on Land (adopted 18 October 1907, entered into force 26 January 1910) 205 CTS 299 (Hague Convention V) article 20. An identical provision was inserted in each of the other conventions adopted at the 2nd Hague Peace Conference, except for Conventions (I)–(III), which are not properly speaking part of the jus in bello.

47  Namely, the Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous or Other Gases, and of Bacteriological Methods of Warfare (signed 17 June 1925, entered into force 8 February 1928) 94 LNTS 65, the High Contracting Parties to which agreed ‘to be bound as between themselves’.

48  Convention Relative to the Treatment of Prisoners of War (adopted 27 July 1929, entered into force 19 June 1931) 118 LNTS 343, article 82. The equivalent provision in article 25 of the contemporaneous Convention for the Amelioration of the Condition of the Wounded and Sick in Armies in the Field (above n 29) contained minor variations in wording but was substantively identical.

49  International Military Tribunal (IMT), Trial of the Major War Criminals before the International Military Tribunal: Nuremberg, 14 November 1945–1 October 1946, Vol XXII (IMT 1948) 472, 474–5.

50  Military and Paramilitary Activities in and against Nicaragua (Nicaragua v United States of America), (Merits) [1986] ICJ Rep 14 para 220.

51  ibid paras 115–116.

52  This may be the case, especially in relation to API and some of the treaties prohibiting or restricting the use of specific weapons.

53  Despite extensive evidence gathered by the UN and various NGOs of IHL violations committed in Yemen in the course of Saudi operations, and sharp criticism within Parliament, the British Government’s response has been to either contest that such violations are occurring, or insist that they are best investigated by the Saudis’ own internal procedures rather than by impartial international mechanisms. For details of alleged IHL violations in Yemen, see UNSC, ‘Final Report of the Panel of Experts on Yemen established pursuant to Security Council Resolution 2140 (2014)’ UN Doc S/2016/73 (26 January 2016) paras 123–142; for domestic British criticism and Government responses, see House of Commons International Development Committee, Crisis in Yemen: Fourth Report of Session 2015–16, HC532 (House of Commons, 4 May 2016) paras 39–73, annex 2 and appendices 1–4.

54  See eg the Swiss-convened Conference of High Contracting Parties to the Fourth Geneva Convention, which resulted in a Declaration (dated 5 December 2001) calling inter alia upon ‘all parties, [whether] directly involved in the conflict or not, to respect and to ensure respect for the Geneva Conventions in all circumstances …’. For the full text of the Declaration, see https://unispal.un.org/DPA/DPR/unispal.nsf/0/8FC4F064B9BE5BAD85256C1400722951. For an overview of the process, which reconvened in 2014 and resulted in another Declaration, see Pierre-Yves Fux and Mirko Zambelli, ‘Mise en œuvre de la Quatrième Convention de Genève dans les Territoires Palestiniens Occupés: Historique d’un Processus Multilateral (1997–2001)’ (2002) 84 IRRC 661; also Matthias Lanz, Emilie Max, and Oliver Hoehne, ‘The Conference of High Contracting Parties to the Fourth Geneva Convention of 17 December 2014 and the Duty to Ensure Respect for International Humanitarian Law’ (2014) 96 IRRC 1115 (including the text of the 2014 Declaration at 1128–30).

55  See eg the Tenth Emergency Special Session of the UN General Assembly (UNGA) (first convened in 1997 and periodically resumed on several occasions since, most recently in 2009), which is concerned specifically with ‘Illegal Israeli actions in occupied East Jerusalem and the rest of the Occupied Palestinian Territory’. A typical early resolution:

[r]ecommends to the States that are High Contracting Parties to the Geneva Convention relative to the Protection of Civilian Persons in Time of War to take measures, on a national or regional level, in fulfilment of their obligations under article 1 of the Convention, to ensure respect by Israel, the occupying Power, of the Convention (UNGA Resolution ES-10/2 UN Doc A/RES/ES-10/2 (25 April 1997) para 8).

56  See eg UNGA, ‘Statement by Ambassador Gabriela Shalev, Permanent Representative of Israel, Tenth Emergency Special Session (resumed)’ (15 January 2009) https://www.un.org/press/en/2009/ga10807.doc.htm.

57  See eg Legal Consequences of the Construction of a Wall in the Occupied Palestinian Territory (Advisory Opinion) [2004] ICJ Rep 136 (Palestinian Wall case), in which the Court found that certain obligations arising under IHL were obligations erga omnes (at para 155), and emphasized the corresponding obligation arising under article 1 of GCIV (at para 158).

58  See eg UNGA Resolution ES-10/15 UN Doc A/RES/ES-10/15 (2 August 2004) paras 1, 7.

59  See David Turns, ‘Implementation and Compliance’, in Elizabeth Wilmshurst and Susan Breau (eds), Perspectives on the ICRC Study on Customary International Humanitarian Law (CUP 2007) 354, 359–60, 372–3.

60  GCI ch VIII; GCII ch VII; GCIII pt VI; GCIV pt IV.

61  API pt V.

62  Protocol Additional to the Geneva Conventions of 12 August 1949, and Relating to the Protection of Victims of Non-International Armed Conflicts (adopted 8 June 1977, entered into force 7 December 1978) 1125 UNTS 609 (APII) article 19.

63  GCI article 47; GCII article 48; GCIII article 127; GCIV article 144; API article 83(1). The GCIII and GCIV articles include particular requirements for personnel with responsibilities for, respectively, prisoners of war and protected persons (ie civilians in occupied territory) to be ‘specially instructed’ as to those Conventions’ provisions; these requirements are amalgamated in API article 83(2). Other modern IHL treaties also include the requirement of dissemination, while limiting it to armed forces: eg Convention on Prohibitions or Restrictions on the Use of Certain Conventional Weapons Which May Be Deemed to Be Excessively Injurious or to Have Indiscriminate Effects (adopted 10 October 1980, entered into force 2 December 1983) (1980) 19 ILM 1523 (CCW) article 6.

64  Among many such initiatives worldwide, prominent examples include the Jean-Pictet Competition http://concourspictet.org/indexen.html, the Martens Moot Court Competition on IHL, and the Israeli Alma National IHL Competition for Students www.alma-ihl.org/ihl-competition. Most such projects are organized by, or at least with the support of, the ICRC at national, regional, and/or international level; for an example of the organization’s approach to IHL civil education, see Luisa Vierucci, ‘Promoting the Teaching of International Humanitarian Law in Universities: The ICRC’s Experience in Central Asia’ (2001) 83 IRRC 155 (and other articles in the same thematic issue).

65  See British Red Cross, ‘Teaching Resources’ www.redcross.org.uk/What-we-do/Teaching-resources.

66  API article 82.

67  For example each of the US services—Army, Navy, Air Force, Marine Corps, and Coast Guard—has its own separate Judge Advocate General’s Corps.

68  See International Institute of Humanitarian Law www.iihl.org.

69  See NATO School Oberammergau www.natoschool.nato.int.

70  See Asia Pacific Centre for Military Law http://apcml.org.

71  See US Department of Defense, ‘Final Report to Congress on the Conduct of the Persian Gulf War, Appendix O—The Role of the Law of War’ (1992) 31 ILM 615, 617.

72  Indeed, although ALS (to take the UK, and more specifically England, as an example) dates in its modern form only from 1948, it traces its genesis back to the authority of the mediaeval offices of Earl Marshal and Advocate of the Army—the origin of the modern term ‘court-martial’, signifying a military court, derives from the Court of the Marshal (or ‘Marshal’s Court’), which was instituted by King Henry VIII in 1521 and was itself based on a much older institution.

73  See Hans-Peter Gasser, ‘Military Manuals, Legal Advisers and the First Additional Protocol of 1977’, in Nobuo Hayashi (ed), National Military Manuals on the Law of Armed Conflict (2nd edn, Forum for International Criminal and Humanitarian Law 2010) 55.

74  See David Turns, ‘Military Manuals and the Customary Law of Armed Conflict’, in Hayashi (above n 73) 65. In this context they are cited by courts in both international and national jurisdictions: see eg the Israeli High Court of Justice’s references to the UK’s military manual in Public Committee against Torture in Israel v Government of Israel (2006) 46 ILM 375.

75  Charles Garraway, ‘Military Manuals, Operational Law and the Regulatory Framework of the Armed Forces’, in Hayashi (above n 73) 45.

76  See eg France Ministry of Defence, Manuel de Droit des Conflits Armés (2012 edn) https://www.defense.gouv.fr/sga/le-sga-en-action/droit-et-defense/droit-des-conflits-armes/droit-des-conflits-armes ; US Department of Defense (DoD), Department of Defense Law of War Manual (June 2015) (Updated December 2016) https://dod.defense.gov/Portals/1/Documents/pubs/DoD%20Law%20of%20War%20Manual%20-%20June%202015%20Updated%20Dec%202016.pdf?ver=2016-12-13-172036-190 .

77  See eg UK Ministry of Defence (MoD), The Joint Service Manual of the Law of Armed Conflict (JSP 383) www.gov.uk/government/uploads/system/uploads/attachment_data/file/27874/JSP3832004Edition.pdf, and its book format (MoD (above n 35)).

78  The German Bundeswehr’s ZDv 15/2—Humanitäres Völkerrecht in bewaffneten Konflikten (1992) has been published in English with extensive academic commentary as Dieter Fleck (ed), The Handbook of International Humanitarian Law (3rd edn, OUP 2013).

79  GCI article 49; GCII article 50; GCIII article 129; GCIV article 146. These provisions are then referred back to in a consolidating clause in API article 85(1). The Protocol also provides for mutual assistance between states parties in criminal matters connected with grave breaches: API article 88.

80  As to the generalities of aut dedere aut judicare, see Questions Relating to the Obligation to Prosecute or Extradite (Belgium v Senegal) (Merits) [2012] ICJ Rep 422, Separate Opinion of Judge Yusuf at paras 18–22; ILC, ‘The Obligation to Extradite or Prosecute (aut dedere aut judicare): Final Report of the International Law Commission’, submitted to the UNGA by the ILC in ‘Report of the International Law Commission on the Work of its 66th Session’ UN Doc A/69/10 (1 May–6 June and 7 July–8 August 2014) para 65.

81  See David Turns, ‘Prosecuting Violations of International Humanitarian Law: The Legal Position in the United Kingdom’ (1999) 4 JACL 1.

82  See David Turns, ‘Aspects of National Implementation of the Rome Statute: The United Kingdom and Selected Other States’, in Dominic McGoldrick, Peter Rowe, and Eric Donnelly (eds), The Permanent International Criminal Court—Legal and Policy Issues (Hart Publishing 2004) 337.

83  GCI article 54; GCII article 45; Protocol Additional to the Geneva Conventions of 12 August 1949, and Relating to the Adoption of an Additional Distinctive Emblem (adopted 8 December 2005, entered into force 14 January 2007) 2404 UNTS 261 (APIII) article 6(1).

84  Eg CCW Amended Protocol II (1996) 35 ILM 1206 article 14.

85  Convention for the Protection of Cultural Property in the Event of Armed Conflict (adopted 14 May 1954, entered into force 7 August 1956) 249 UNTS 240 (1954 Convention) article 3. This Convention also entails dissemination in terms virtually identical to those of the Geneva Conventions (ibid article 25); the production of quarterly reports to the Director General of the UN Educational, Scientific and Cultural Organisation ‘concerning any measures being taken, prepared or contemplated’ in fulfilment of the Convention (ibid article 26(2)); and the enactment of penal or disciplinary sanctions in domestic criminal law for violations of the Convention (ibid article 28). See further the Second Protocol to the Hague Convention of 1954 for the Protection of Cultural Property in the Event of Armed Conflict (adopted 26 March 1999, entered into force 9 March 2004) 2253 UNTS 172 articles 5, 11, 15–21.

86  API article 60(2).

87  Yves Sandoz, Christophe Swinarski, and Bruno Zimmermann (eds), Commentary on the Additional Protocols of 8 June 1977 to the Geneva Conventions of 12 August 1949 (ICRC/Martinus Nijhoff 1987) (AP Commentary) para 2308.

88  API article 36. For discussion, see Justin McClelland, ‘The Review of Weapons in Accordance with Article 36 of Additional Protocol I’ (2003) 85 IRRC 397; Kathleen Lawand, A Guide to the Legal Review of New Weapons, Means and Methods of Warfare: Measures to Implement Article 36 of Additional Protocol I of 1977 (ICRC 2006).

89  See MoD, ‘UK Weapons Reviews’ (Development, Concepts and Doctrine Centre) www.gov.uk/government/uploads/system/uploads/attachment_data/file/507319/20160308-UK_weapon_reviews.pdf.

90  For general discussion, see Olivier Bangerter, ‘Reasons Why Armed Groups Choose to Respect International Humanitarian Law or Not’ (2011) 93 IRRC 353.

91  API article 1(4).

92  ibid article 96(3).

93  For discussion of the UK’s reservation to API in respect of articles 1(4) and 96(3) prompted by the situation in Northern Ireland, and the failure of the Palestine Liberation Organization to have its 1989 declaration accepted in relation to its struggle against Israel, see Turns, ‘The Law of Armed Conflict’ (above n 32).

94  See eg ICRC, ‘A Collection of Codes of Conduct Issued by Armed Groups’ (2011) 93 IRRC 483 (examples from China, the Philippines, Colombia, Uganda, Sierra Leone, and Libya).

95  See Pascal Bongard and Jonathan Somer, ‘Monitoring Armed Non-State Actor Compliance with Humanitarian Norms: A Look at International Mechanisms and the Geneva Call Deed of Commitment’ (2011) 93 IRRC 673.

96  For a useful overview of the typology of such commitments, see Sandesh Sivakumaran, ‘Lessons for the Law of Armed Conflict from Commitments of Armed Groups: Identification of Legitimate Targets and Prisoners of War’ (2011) 93 IRRC 463 at 465–9.

97  API article 43(1). The internal disciplinary system of armed forces will typically be enforced by military police or provost-marshals, with investigations of cases where crimes appear to have been committed and subsequent prosecution in courts-martial or civilian courts, as appropriate. The military legal and disciplinary system in the UK is provided for in the regulations promulgated for each service (eg The Queen’s Regulations for the Army 1975 www.gov.uk/government/uploads/system/uploads/attachment_data/file/433769/QR_Army.pdf, with similar but separate regulations existing for the Royal Navy and the Royal Air Force) and the tri-service Armed Forces Act 2006.

98  For an overview of the doctrine, see Guénaël Mettraux, The Law of Command Responsibility (OUP 2009).

99  API article 86(2).

100  ibid article 87.

101  Rome Statute of the International Criminal Court (adopted 17 July 1998, entered into force 1 July 2002) 2187 UNTS 3 (Rome Statute) article 28.

102  For an early modern Anglo-Australian example, see the case of Lieutenants Harry Morant, Peter Handcock, and George Witton of the Bushveldt Carbineers, court-martialled and executed for the murder of prisoners of war during the Second Boer War: The Brisbane Courier (24 May 1902).

103  For an early American example, see Trial of Henry Wirz (1865), US House of Representatives, 40th Congress, 2nd Session, Ex Doc No 23.

104  This jurisdiction is based exclusively on national legislation. For instance, in the UK it is currently provided for by the International Criminal Court Act 2001, pt 5 (Offences under domestic law) and the Armed Forces Act 2006; in the US, by the Uniform Code of Military Justice (1950) 10 USC paras 802, 805, 877–934.

105  United States v William L Calley, Jr (US Court of Military Appeals, 21 December 1973) 22 USCMA 534.

106  Reg v Blackman (UK Courts Martial Appeal Court) [2014] EWCA Crim 1029 (22 May 2014).

107  The International Criminal Tribunal for the Former Yugoslavia, established by UNSC Resolution 827 UN Doc S/RES/827 (25 May 1993); the International Criminal Tribunal for Rwanda, established by UNSC Resolution 955 UN Doc S/RES/955 (8 November 1994).

108  For instance, the Special Court for Sierra Leone (established in 2000) and the Special Court for Kosovo.

109  The Prosecutor v Thomas Lubanga Dyilo (Judgment) ICC-01/04-01/06, T Ch I (14 March 2012).

110  The Prosecutor v Ahmad Al Faqi Al Mahdi (Decision on the Confirmation of Charges) ICC-01/12-01/15, Pre-Trial Ch I (24 March 2016).

111  GCI, GCII, and GCIII article 8; GCIV article 9; API article 5.

112  Current examples are the Swiss diplomatic representation of American and Saudi interests in Iran and of Russian interests in Georgia, and the Swedish representation of American, Australian, and Canadian interests in North Korea.

113  See Howard S Levie, ‘Prisoners of War and the Protecting Power’ (1961) 55 AJIL 374.

114  Switzerland acted for the UK, while Brazil acted for Argentina. See ICRC, Commentary on the First Geneva Convention: Convention (I) for the Amelioration of the Condition of the Wounded and Sick in Armed Forces in the Field (2nd edn, ICRC 2016) paras 1115–1119.

115  GCI article 10. This has been the case, for instance, in respect of Russia and Georgia since their brief conflict over South Ossetia and Abkhazia in 2008.

116  GCIII article 126.

117  GCIV article 143.

118  ibid article 14.

119  See eg ICRC, ‘Iran/Iraq Memoranda of 7 May 1983 and 10 February 1984’ (Case Study, 12 January 2012) https://casebook.icrc.org/case-study/icrc-iraniraq-memoranda.

120  API article 90.

121  For further details of the IHFFC’s mandate and work, see IHFFC, www.ihffc.org/index.asp?Language=EN& page=home.

122  One of the best-known examples is TH O’Sullivan’s ‘The Harvest of Death’, depicting the bloated and contorted bodies of Federal soldiers killed at the Battle of Gettysburg in 1863.

123  ‘Lawfare’ has been defined as, ‘the strategy of using—or misusing—law as a substitute for traditional military means to achieve and operational objective’: Charles J Dunlap, ‘Lawfare Today: A Perspective’ (Winter 2008) Yale J Int’l Affairs 146, 146.

124  See Richard Ekins, Jonathan Morgan, and Tom Tugendhat, Clearing the Fog of Law—Saving Our Armed Forces from Defeat by Judicial Diktat (Policy Exchange 2015).

125  The phrase was coined by Lord Hope in Smith and Others v Ministry of Defence [2013] UKSC 41, [2013] 2 WLR 27; see also Richard Scorer, ‘The Judicialisation of War?’ (2013) 163(7571) NLJ.

126  See eg UN Human Rights Council (HRC), ‘Report of the Commission of Inquiry on Lebanon pursuant to Human Rights Council Resolution S-2/1’ UN Doc A/HRC/3/2 (23 November 2006); UNHRC ‘Report of the United Nations Fact-Finding Mission on the Gaza Conflict UN Doc A/HRC/12/48 (15 September 2009); UN, ‘Report of the Secretary-General’s Panel of Experts on Accountability in Sri Lanka’ (31 March 2011) https://www.securitycouncilreport.org/atf/cf/%7B65BFCF9B-6D27-4E9C-8CD3-CF6E4FF96FF9%7D/POC%20Rep%20on%20Account%20in%20Sri%20Lanka.pdf.