Introduction
In recent times – as the armed conflict in Syria demonstrates – there have been a number of attacks against hospitals and medical installations.Footnote 1 Hospitals and installations are protected under international humanitarian law (IHL) unless they are used for “acts harmful to the enemy” (AHTTE).Footnote 2 Belligerents are under an obligation to grant so-called “special protection” to “medical personnel, units and transports”Footnote 3 on account of their humanitarian function in order to ensure medical care for the wounded and sick, or shipwrecked, in all circumstances. This “special protection” is a lex specialis (though not of a derogable nature) with regard to the so-called “general protection” of civilian persons under Articles 48 and 51 of Additional Protocol I to the four Geneva Conventions of 1949 (AP I), and civilian objects under Article 52(2) of AP I, with their related customary international law norms. General protection is lost when an object becomes a military objective. Simply put, this is the case when that object makes a military contribution to the enemy and its destruction or neutralization offers a military advantage to the attacking belligerent. Conversely, objects under special protection are normally placed under some higher threshold regarding the loss of protection. In the case of medical services, this occurs when these carry out AHTTE and after a warning has remained unheeded.
The 1949 Geneva Conventions and their 1977 Additional Protocols do not define the notion of AHTTE,Footnote 4 nor the precise consequences of a loss of special protection.Footnote 5 The present paper tries to partially fill this gap by offering a more in-depth legal analysis on the notion of “acts harmful to the enemy” in relation to medical servicesFootnote 6 and its precise relations to other relevant notions of IHL.Footnote 7 It will be centred on land warfareFootnote 8 and more particularly on the legality of military attacks,Footnote 9 to the exclusion of lawful capture of medical personnel in case of AHTTE. The latter situation is not specifically relevant for an analysis of AHTTE: the personnel captured retain their legal statusFootnote 10 and are protected under the rules on retention.Footnote 11 What is specific to AHTTE is that under some circumstances the adverse belligerent is allowed to attack a medical unit. It is in this perspective that the notion of AHTTE has been shaped, and in this perspective that it must be scrutinized and interrogated in the first place. This, then, is the punctum saliens of the present article.
Before delving into the subject matter, some preliminary definitions of the relevant notions – notably, “special protection”, “medical personnel” and “medical units and transports” – are discussed, followed by an analysis of the conditions for the loss of special protection. The notion of AHTTE is then examined through its negotiating history and its relations with other concepts of IHL, such as “perfidy”, “direct participation in hostilities” and “military objective”. Building on the distilled findings, the consequences of the loss of special protection, as a result of AHTTE and not heeding a warning, are explored. Lastly, specific recommendations are provided on how to interpret the rules that govern an attack, considered prima facie lawful, on a hospital.
Special protection
Medical personnel, units and transports, as well as the wounded and sick, are entitled to protection against direct attack in both international armed conflict (IAC) and non-international armed conflict (NIAC). This special protection is granted by a series of specific rules of IHL.Footnote 12 Originally, IHL only protected “wounded and sick” combatants;Footnote 13 today, civilians are included in that notion. Indeed, AP I established a uniform protective regime.Footnote 14 To be wounded or sick under IHL, two cumulative criteria have to be fulfilled: (1) a person must require medical care; and (2) he or she must refrain from any act of hostility.Footnote 15 Thus, wounded or sick persons who commit an “act of hostility”Footnote 16 (to be defined below) do not qualify as such under IHL and do not benefit from the protective regime granted to this category of persons.Footnote 17 The legal status of being wounded or sick therefore depends as much on a person's actual conduct as on their medical condition. This binary definition is relevant for both IAC and NIAC.Footnote 18
The notion of “medical personnel” was similarly extended to cover both military personnel and civilians.Footnote 19 Under contemporary IHL, the definition, which builds upon Articles 24–26 of Geneva Convention I (GC I) and Article 20 of Geneva Convention IV (GC IV), is codified in Article 8(c) of AP I. Qualifying as medical personnel under IHL supposes again the fulfilment of two cumulative criteria: (1) medical personnel must be assigned to their medical duties by a party to the conflict under whose control they are placed;Footnote 20 and (2) the assignment, whether temporary or permanent, must be exclusive – i.e., limited to the “search for, collection, transportation, diagnosis or treatment, including first-aid treatment, of the wounded, sick and shipwrecked, and the prevention of disease”Footnote 21 – for all the time that the person is assigned to medical tasks. This definition is considered applicable in both IAC and NIAC,Footnote 22 subject to the differences resulting from the presence of non-State armed groups. When civilian medical personnel do not fulfil the conditions set out above, they may still be protected against attacks by the general protection accorded to civilians.Footnote 23
Protected objects are in the first place “medical units and transports”, extending once again to both military and civilian ones.Footnote 24 Special protection is restricted to medical units and transports that are assigned to medical purposes by a party to the conflict. Unauthorized medical units or transports are protected according to the rules on the protection of civilian objects (general protection). Again, these rules are regarded to be applicable in both IAC and NIAC.Footnote 25 Both military and civilian medical objects are also under the purview of protection as civilian objects (AP I, Article 52).Footnote 26 Civilian objects are negatively defined as “all objects that are not military objectives”.Footnote 27 This is manifestly the case for both military and civilian medical units and transports.
The notion of special protection entails the substantive obligation to “respect and protect”. This term was first introduced in treaty law in the 1906 Geneva ConventionFootnote 28 governing land warfare to safeguard the immunity, inviolability and neutrality enjoyed by ambulances, medical personnel and, by implication, the wounded and sick. The obligation to respect entails a series of obligations of a negative nature, notably to refrain from attacking protected persons. The obligation to protect implies a series of obligations of a positive nature – i.e., to take measures for the benefit of the protected persons.Footnote 29 This double obligation applies both in the relationships between a party to the conflict and the protected persons of the enemy, and in those with persons of its own armed forces.Footnote 30 Special protection of persons or units applies “in all circumstances”Footnote 31 except when acts are committed for hostile purposes or with effects which harm the adverse party. The formulation indicates that operational reasons or military necessity cannot be invoked, as such, to justify non-compliance.Footnote 32 The obligation exists regardless of whether or not the enemy complies with it;Footnote 33 belligerent reprisals are prohibited against protected persons in both IAC and NIAC.Footnote 34
The main aspect of special protection relevant for the present article relates to the prohibition against attacking protected persons and objects. This obligation concerns in the first place direct attacks on such persons or objects, but the question is also whether in attacking some military objective the proportionality rule requires us to take account of the collateral losses to military medical personnel and installations (it is clear that the collateral losses to civilian medical personnel and objects must be taken into account). The answer to this question is controversial.Footnote 35 For some, the proportionality restriction fully applies also in this context.Footnote 36 There would be no apparent reason why the obligations under special protection should be limited to direct attacks and not extended to the conduct of hostilities in general. It would also be inadequate to conclude that specially protected persons should enjoy a lesser degree of protection than ordinary civilians.Footnote 37 Moreover, the opposite interpretation would hamper the fulfilment of the purpose of special protection: in order to provide medical care to the wounded and sick, the personnel and objects dedicated to that task have to operate in proximity of the fighting, and it is thus essential to uphold their protection against incidental harm. For some other authors, the obligation applies but the equation may be slightly more lenient than the one for civilian collateral damage, on account of the military nature of the personnel and objects at stake, especially in the midst of combat operations.Footnote 38 Lastly, there are authors denying that the proportionality requirement applies to military medical personnel and objects, or to the military wounded and sick, those persons remaining combatants.Footnote 39
The first or second view are the better ones: there is no reason to consider that protected persons, including those placed hors de combat, are protected less than civilians. On the contrary, IHL provides for obligations not to attack such persons,Footnote 40 notwithstanding their combatant status; when such an obligation against direct attack is stipulated, the lesser obligation not to exceed in collateral damage against these persons must be considered a fortiori as being contained in the main rule against attack (i.e., special protection). This is all the more true given that the principle of precautions in attack (as enshrined in Article 57 of AP I) undisputedly applies to such persons and objects.Footnote 41 The obligation of precaution requires a belligerent to take measures to minimize collateral damage. Some provisions in Article 57 of AP I even make explicit reference to special protection, notably its paragraphs (2)(a)(i) and (2)(b), though such reference is not made in the paragraphs dealing with proportionality issues.Footnote 42
Let us now turn to the question of how special protection, an integral component of it being protection against direct attack, relates to general protection – i.e., what is the legal difference between the protection against attack under special protection and under general protection (as civilian objects)? The first point to be noted is that special protection does not technically derogate from general protection.Footnote 43 Both military and civilian medical units are at once civilian objects under the definition of Article 52 of AP I, and specially protected objects under the relevant provisions of IHL. There are two layers of protection which add up one to the other; if one protection disappears for some reason, e.g. because a medical unit has become a military objective, which eliminates the general protection, there remains the layer of the special protection, with its own requirements for the loss of immunity against attack (to be explained below). Conversely, if a medical object loses its special protection because it is used for AHTTE, it may remain a civilian object and entitled to the general protection against attack unless the usage for AHTTE converts it into a military objective. We are thus not in a configuration of lex specialis derogat legi generali; it would rather be lex specialis “completat” legi generali.
The second point to be noted is that special protection is somewhat more stringent than general protection. For the loss of the latter, a military contribution and a military advantage in destruction or neutralization (objects) or a direct participation in hostilities (persons) are sufficient; for the loss of the former, in principle, an advance warning must be issued, with a reasonable time limit provided for the warning to be observed whenever possible, and an ascertainment that the warning was not heeded made, before an attack against the medical services that have become military objectives are carried out. Notice that the latter must have become military objectives under Article 52(2) of AP I in order to allow an attack – it is not sufficient that they commit any type of AHTTE. For an attack, the legal standard to be applied comes from the regime of general protection and not from the one of special protection. If AHTTE are committed, a series of responses may be carried out, such as capture of a medical unit having indulged in such acts; but if an attack is to be performed, the object to be attacked must in any case be a military objective. This is so because Article 52(2) of AP I indicates in an exhaustive manner when an object can be attacked. To these conditions under general protection, the ones under special protection (warning, etc.) must be added. For the moment, we may thus conclude that the rules granting special protection result in a higher threshold for the loss of protection against attack with regard to persons and objects under special protection in comparison with those just under general protection. We may now turn to a closer analysis of the conditions for the loss of special protection.
Loss of special protection
The special protection granted to medical services is “fundamental but not absolute”.Footnote 44 IHL takes into account the fact that parties to a conflict may be tempted to abuse their special status in order to commit AHTTE.Footnote 45 By way of illustration, “[d]uring the Second World War, members of the medical personnel in occupied territories sometimes concealed combatants in hospitals and helped them carry out military missions, such as intelligence activities and sabotage”.Footnote 46 These conducts may lead to a loss of special protection of these medical personnel and these hospitals. Such loss is considered an “exception”,Footnote 47 which is linked to the medical services’ definitional requirement that they are “exclusively assigned to medical duties [in order] to be accorded respect and protection”.Footnote 48 What are the exact conditions for such a loss of special protection?
First condition: AHTTE outside of humanitarian function
The first condition is that medical services commit AHTTEFootnote 49 outside their humanitarian function.Footnote 50 For IAC, Article 21 of GC I provides for the loss of protection for military medical establishments and units, Article 19(1) of GC IV for civilian hospitals, Article 13(1) of AP I for civilian medical units, and Article 21 of AP I for civilian medical vehicles.Footnote 51 The phrase “humanitarian function” adopted in the Additional Protocols replaces “humanitarian duties” in the Geneva Conventions.Footnote 52 For NIAC, Article 11(2) of Additional Protocol II (AP II) provides for the loss of protection for medical units and transports. Here the phrase AHTTE is replaced with “hostile acts”. The meaning of the two phrases “AHTTE” and “hostile acts” is essentially the same.Footnote 53 The loss of special protection pertaining to medical personnel is nowhere expressly stated in IHL. The rules specifically applicable to the discontinuance of special protection pertaining to medical units are “applied by analogy to medical personnel”.Footnote 54
The provisions, both in treaty law and customary law, that govern the consequences of the commission of AHTTE by medical units and transports, and by analogy medical personnel, refer only to “loss of protection”, not “loss of special protection”. At first reading, a question arises as to what this loss really entails. Does it mean that these medical services lose their entitlement of being granted some treatment by the adverse party – the obligation to protect, but not respect (partial loss of special protection), or the obligation to protect and respect (full loss of special protection)? Does it lead to a loss of protection against direct attack? To consider that the loss is limited to the obligation to protect is too narrow an interpretation. This would not be feasible in practice, as “it is frequently impossible to clearly separate the obligation to ‘respect’ from the obligation to ‘protect’”.Footnote 55 To consider that the loss automatically results in the loss of protection against direct attack is, on the other hand, too wide an interpretation. AHTTE come in a wide range of different forms, and not all of them would be sufficiently grave for such a loss.Footnote 56 Even when the special protection is lost, it should be recalled that civilian medical personnel and medical objects retain their general protection unless engagement of AHTTE converts the person or object into a military objective. Thus, an interpretation that the loss of special protection automatically transforms the medical services in question into lawful targets is not sound. Summing up the foregoing, the loss should be interpreted as a loss of “special protection”, encompassing both the obligation to protect and respect, with a remark that it does not inevitably extend into a loss of protection against direct attack.
The separate notion of “outside their humanitarian function” is not defined under IHL,Footnote 57 but it does not give rise to particular problems of interpretation, as the functions of medical services are clearly defined.Footnote 58 It is simply a negative definition of the medical services’ function enumerated under IHL. The conduct of medical services going beyond these duties may, depending on the circumstances, qualify as AHTTE outside their humanitarian function, which could entail a loss of special protection.Footnote 59 This understanding leads to an interpretation that “[e]ven if a particular type of conduct may appear to constitute an ‘act harmful to the enemy’, it will still not result in a loss of special protection where it remains within the humanitarian duties”Footnote 60 of the medical services. Obviously, the nursing of wounded and sick armed forces or combatants,Footnote 61 which “enables them to return to the battlefield”,Footnote 62 is considered a humanitarian function, as is “assistance with the health planning aspects of the military operation and involvement in the transmission of the health details of enemy patients, even though in some circumstances this information may have military value”.Footnote 63 Other factual scenarios of conduct that appears to be AHTTE but remains within the humanitarian function include “a mobile medical unit accidentally break[ing] down while it is being moved in accordance with its humanitarian function, and thereby obstruct[ing] a crossroads of military importance”.Footnote 64 Similarly, “the presence or activities of a medical unit might interfere with tactical operations”Footnote 65 due to the unit's proximity to the battlefield, “its lights at night”,Footnote 66 or the use of X-ray apparatus emitting radiation that could interfere with the military radio communications of the enemy.Footnote 67 These conducts are compatible with the medical services’ humanitarian function and do not deprive them of their special protection.Footnote 68 However,
from a practical perspective, once such an act is identified as being harmful to the adversary, reasonable action should be taken to remedy the issue as soon as possible so as to not unnecessarily jeopardise the safety of the wounded and sick being cared for by the medical units.Footnote 69
AHTTE must be committed outside the medical services’ humanitarian function, but this does not lead to a conclusion that only acts deliberately committed to harm the adversary constitute AHTTE. Acts which could accidentally have an unfavourable effect on the enemy are arguably included as well (to be explained below).
Second condition: A warning and a time limit, the warning remaining unheeded
The second condition to be met in order for the special protection to cease is established in the same treaty law provisions stipulating the first condition. Special protection granted to the medical units “may, however, cease only after a due warning has been given, naming, in all appropriate cases, a reasonable time limit and after such warning has remained unheeded”.Footnote 70 Thus, in the first place, a warning must be given.Footnote 71 The aggrieved party to the conflict must inform the medical service that
the latter has committed, or is committing, an act harmful to it, or that there are reasonable grounds for suspicion that such acts have been or are being committed, and that it is in danger of being attacked or subjected to an enforcement measure if it does not put an end to the activity in question.Footnote 72
The purpose of issuing a warning is to allow those engaging in AHTTE to terminate those acts or at least to evacuate the wounded or sick.Footnote 73 The underlying assumption is that medical services will normally not engage in harmful acts and that such acts, if committed, may have been caused either by mistake or negligence. In this regard, the warning requirement reflects the principle of necessity as ultima ratio: if no warning is given, it cannot be said that the attack was really necessary to curb the harmful acts; a request to that effect could indeed have been heeded. Conversely, the absence of a warning is an exception “in the extreme circumstances of an immediate threat to the lives of advancing combatants, where it is clear that a warning would not be complied with”.Footnote 74 The provisions do “not specify what is meant by a ‘due warning’, including what form it must take”.Footnote 75 Whatever the method selected, in order to achieve the purpose, the “warning should be clear and specific, and it should mention the harmful act in which the unit, establishment, or personnel is engaged”.Footnote 76
Then, in the second place, when possible, a reasonable time limit for ceasing the harmful acts must be indicated. Sometimes, however, no delay in the response is possible. The often-mentioned example is “a body of troops approaching a hospital” who are “met by heavy fire from every window”;Footnote 77 “[i]n such a case, after the issuance of a warning, fire could be returned without delay”.Footnote 78 When a reasonable time limit is appropriate, it “must be long enough to achieve the purpose of a warning”:Footnote 79 that is, to allow those in charge of the medical services “enough time to reply to the accusations that have been made”;Footnote 80 “depending on the circumstances, to change their approach, to explain themselves if a mistake has been made”;Footnote 81 to cease the unlawful acts;Footnote 82 or to evacuate the wounded and sick.Footnote 83
Lastly, the warning must have remained unheeded. When the medical services ignore the warning issued by the aggrieved party to the conflict – i.e., “where the act harmful to the enemy is not terminated”Footnote 84 – the relevant provisions relieve the obligation of the aggrieved party to respect and protect that specific medical service. Note again that the commission of AHTTE leads to the loss of special protection but conducting an attack against medical units or transports still requires the aggrieved party to satisfy Article 52(2) of AP I. Subsequent attacks or enforcement measures should be effective in inducing the adverse party to respect the law and should be proportionate to the committed AHTTE that the aggrieved party aims to stop. Such measures cannot be punitive in nature; they must be merely protective. The provisions do not specify “the measures that the aggrieved Party to the conflict is allowed to take if the warning remains unheeded”;Footnote 85 neither is it clear whether the aggrieved party may take some measures short of an attack even if the warning has been heeded.Footnote 86 Measures short of an attack that could be taken by the aggrieved party to the conflict include search operations or capture for medical units and transports, and interrogation, arrest or detention for medical personnel.Footnote 87 Although IHL does not specifically prohibit such measures against these medical services, whenever feasible, the way that these operations are conducted should be closely regulated, and practical measures should be developed to minimize the negative effects of health-care delivery in armed conflicts.Footnote 88
Summing up, AHTTE may have legal consequences even if the warning has been heeded,Footnote 89 which constitutes in part a sanction of their hostile attitude. But an attack is excluded in such cases, since the latter can only be protective in nature and no necessity exists any more in this regard once the warning has been heeded. Notice also that when medical units and transports have ceased their AHTTE, they automatically also lose their status as a military objective under Article 52 of AP I.Footnote 90 This is so because if there are no AHTTE, there is a fortiori no contribution to military operations, which is a definitional element of the military objective.
What if the warning is partially heeded? The attack should then be proportionate to the committed AHTTE, taking into consideration the concrete context of circumstances, including the (partial) response of the medical services and the conditions of the wounded and sick. In other words, the question here is one of full context viewed in the light of the principles of necessity and proportionality.
For NIAC, the San Remo Manual on the Law of Non-International Armed Conflict confirms: “An opportunity must be given to the other side to abide by the rules, and an attack can only be made if it is clear that the warning has been ignored.”Footnote 91 The question has arisen as to whether the warning requirement also exists under customary international law for NIACs. Strictly speaking, for the International Committee of the Red Cross's (ICRC) Customary Law Study, the warning procedural requirements are not obligatory in a NIAC for States that have not ratified AP II.Footnote 92 It should be recalled, however, that this study “did not distinguish between the two categories of non-international armed conflict [AP II and Article 3 common to the four Geneva Conventions] because it was found that States did not make such a distinction in practice”.Footnote 93 Some warning obligation could perhaps be implied in common Article 3, which reflects customary law, though that is uncertain. The question as to the reach of customary international law on this issue consequently remains debatable.
Finally, the jurisprudence of the International Criminal Tribunal for the former Yugoslavia (ICTY) in the Galić caseFootnote 94 sheds some light on the warning obligation. In this case, the lawfulness of shell attacks by a belligerent directed against a hospital was discussed.Footnote 95 The hospital, while still treating the wounded and sick, had become a “military base”Footnote 96 from which weapons were being fired by the adverse belligerent against this belligerent.Footnote 97 The Appeals Chamber asserted that a hospital becomes a legitimate target when used for hostile or harmful acts unrelated to its humanitarian function.Footnote 98 However,
relying on relevant provisions of AP I (Article 13(1)) and AP II (Article 11(2)), the Appeals Chamber qualified the loss of protection by requiring that an advance warning be given of an attack. In its view, the lack of a due warning, including a reasonable time period for compliance, would render any subsequent attack unlawful, despite the fact that the protected object constituted a military objective.Footnote 99
The notion of “acts harmful to the enemy”
Negotiating history
The concept of AHTTE – though differently worded – was introduced for the first time in treaty law in Article 7 of the 1906 Geneva Convention, specifying that the protection of sanitary formations and establishments ceases if they are used to commit “acts injurious to the enemy”.Footnote 100 Still in 1949, AHTTE was not defined in any meaningful sense. As was stated at the 1949 Diplomatic Conference:
The term acts harmful to the enemy is perhaps not very elegant. We endeavoured to find a better wording; but we returned to the traditional expression …. The expression is, perhaps, somewhat elastic, but it seems to us clear. It covers not only acts of warfare proper but any activity characterizing combatant action.Footnote 101
The ICRC's alternative wording, expressing the same idea for AHTTE in preparation for the Diplomatic Conference, was “acts the purpose or effect of which is to harm the adverse Party, by facilitating or impeding military operations”.Footnote 102 Jean Pictet in 1985 wrote that “[s]uch acts [AHTTE] have the aim or effect, by favouring or impeding military operations, of being detrimental to one of the belligerents”.Footnote 103 In the context of Article 13(1) of AP I, the ICRC Commentary explains that “the definition of harmful is very broad. It refers not only to direct harm inflicted on the enemy, for example, by firing at him, but also to any attempts at deliberately hindering his military operations in any way whatsoever”.Footnote 104
Conducts amounting to AHTTE
Examples of AHTTE leading to the loss of special protection for medical units include “firing at the enemy for reasons other than individual self-defence”,Footnote 105 “installing a firing position in a medical post”,Footnote 106 “the use of a hospital as a shelter for able-bodied combatants or fugitives, as an arms or ammunition dump, or as a military observation post”,Footnote 107 the use of a hospital “as a centre for liaison with fighting troops”Footnote 108 and “the placing of a medical unit in proximity to a military objective with the intention of shielding it from the enemy's military operations”.Footnote 109 This last act is specifically prohibited under Article 12(4) of AP I. Examples of AHTTE leading to the loss of special protection for medical transports include “the use of the vehicle as a mobile military command post or as a base from which to launch an attack”Footnote 110 and “the transport of healthy troops, arms or munitions”.Footnote 111 Moreover, prohibited acts of medical aircraft under Article 28(1)–(2) of AP I apply not only to medical aircraft but also, by analogy, to any persons and objects enjoying special protection.Footnote 112 Although the phrase “acts harmful to the enemy” is not explicitly used, these are analogous forms of abuseFootnote 113 with regard to the medical aircraft's protected status.Footnote 114 Thus, they can be applied by analogous reasoning to the medical services on land. The analogous application of this rule to medical units and transports is that these services will lose their special protection if they are used “to attempt to acquire any military advantage over an adverse party”, “to attempt to render military objectives immune from attack”, “to collect or transmit intelligence data” or “to carry any persons or cargo not related to medical function”.Footnote 115 Finally, examples of AHTTE leading to the loss of special protection for medical personnel include when such personnel “take up arms for offensive or for non-recognized defensive purposes”,Footnote 116 “[assist] in the operation of a weapon system or in the planning of a military operation, or [transmit] intelligence of military value”,Footnote 117 or “help able-bodied combatants of their State to hide for a while in a hospital”.Footnote 118
Some recent examples of AHTTE can be found in the ICRC's Health Care in Danger report,Footnote 119 which identifies the fact that “[h]ealth-care facilities were occupied and subject to misuse”Footnote 120 as one of its most important findings. Misuse includes “any use for purposes other than the exclusive function of providing health care”.Footnote 121 This is a broader definition than AHTTE, as not every misuse is militarily harmful. The ICRC report documents misuse in several forms, including military occupation and/or military bases established in such facilities, services used by a belligerent for shelter from the adverse belligerent's attacks (mainly in a context identified as one of active fighting), installation of weapons, and launching of attacks.Footnote 122 These conducts transform these health-care facilities into “objects serving military purposes”Footnote 123 and can thus be considered as AHTTE. Other forms of misuse have also been documented, including military personnel camping in the facility for a limited time, guarding the facility in order to conduct interrogations and identify opposition fighters, and keeping hostages and exercising ill-treatment.Footnote 124 For these conducts, further facts must be contextually assessed to establish whether the relevant conduct amounts to AHTTE.
Another more complicated question relates to when the wounded and sick are interrogated or tortured inside medical units. Would these conducts qualify as AHTTE, and if so, what would be the legal consequences? During the Iraq War in 2003, the US military commanders were advised that “the questioning of Iraqi detainees and EPWs [enemy prisoners of war] beyond the legally required identification information on board U.S. hospital ships during armed conflict might strip the ship of its protected status under GWS-Sea [Geneva Convention II], article 22”.Footnote 125 The ICRC Commentary on Article 34 of Geneva Convention II (GC II) takes the position that “the interrogation of enemy prisoners of war on board hospital ships, when the said interrogation seeks to acquire information beyond what they are required to disclose on the basis of Article 17 of the Third [Geneva] Convention”,Footnote 126 would qualify as AHTTE. This interpretation would apply by analogy to medical units on land. In the same vein, when the wounded and sick are subjected to prohibited torture and cruel, inhuman or degrading treatment inside medical facilities, this would arguably qualify as AHTTE as well. In these mistreatment cases, proportionate enforcement measures to respond to the harmful acts against the medical service in question, such as armed entry, inspection or capture, could be made. Whether these harmful conducts would justify a direct attack against the medical facility would then be subject to the rules on the conduct of hostilities. In most cases, these rules, together with the overarching obligation to protect and respect the wounded and sick, would render such an attack unlawful.
As evinced in the aforementioned examples, “[t]he notion of acts harmful to the enemy, despite the plural form, presumably applies to a singular act”.Footnote 127 There is indeed no reason to exclude single acts from the purview of the exception, all the more since a single AHTTE can be of significant gravity. AHTTE is restricted to specific “conducts” – i.e., “a person's behaviour in a particular place or in a particular situation”Footnote 128 – and in principle, specific conducts relevant to AHTTE should not be blurred with other conducts that are not. Otherwise, this could inherently enlarge the scope of the loss of special protection to medical persons or objects that have not been used to commit AHTTE. Furthermore, AHTTE supposes “use for military purposes”. The idea that hospitals lose protection when being used for military purposes can be traced back to Article 27 of the 1907 Hague Convention IV.Footnote 129 The law does not elaborate on the degree of use, the frequency or the gravity; any use of the medical services by a party to the conflict for military purposes may be considered an act harmful to the enemy,Footnote 130 and a threshold for severity, including volume, duration or intensity, is not required. Neither does the use necessarily need to be continuous or regular; it could be singular, sporadic or irregular. Even indirect, accidental or attemptedFootnote 131 use is arguably included.Footnote 132 Conversely, there are also conducts that do not constitute AHTTE. Examples of such acts are codified in Article 22 of GC I for military medical units and establishments, Article 19(2) of GC IV for civilian hospitals, and Article 13(2) of AP I for civilian medical units.Footnote 133 Article 13(2) of AP I reads:
The following shall not be considered as acts harmful to the enemy:
a) that the personnel of the unit are equipped with light individual weapons for their own defence or for that of the wounded and sick in their charge;
b) that the unit is guarded by a picket or by sentries or by an escort;
c) that small arms and ammunition taken from the wounded and sick, and not yet handed to the proper service, are found in the units;
d) that members of the armed forces or other combatants are in the unit for medical reasons.
This list is not exhaustive.Footnote 134 The analogous application of this rule to medical personnel implies that
it is not to be considered a hostile act if medical personnel are escorted by military personnel or such personnel are present or if the medical personnel are in possession of small arms and ammunition taken from their patients and not yet handed over to the proper service.Footnote 135
The list mentioned above is not applicable to NIAC and AP II, but it can serve as a basis for interpretation of the lawFootnote 136 and also for the determination of customary international law. Let us look more closely at these conducts not constituting AHTTE.
Articles 13(2)(a) of AP I and 22(1) of GC I regulate that medical personnel may be armed and that they may, in case of need, use these arms to defend either themselves or the wounded and sick in their charge against unlawful violence.Footnote 137 This would not constitute AHTTE. Article 22(1) of GC I does not specify the type of arms that medical personnel could lawfully use,Footnote 138 but Article 13(2)(a) of AP I limits it to “light individual weapons”.Footnote 139 “Any use going beyond these permitted purposes, even with ‘light individual weapons’”,Footnote 140 or when medical personnel are equipped with “any weapons heavier than those stipulated”,Footnote 141 would constitute AHTTE. Examples of AHTTE by medical personnel include using light individual “weapons in combat against enemy forces acting in conformity with the law of war, notably to resist capture”,Footnote 142 “carrying weapons which are portable by one individual yet which go beyond the purpose of self-defence, such as a man-portable missile or an anti-tank missile”,Footnote 143 and installing “heavy weapons, such as ‘crew-served’ machine guns (requiring a team of at least two people to operate them)”,Footnote 144 on a medical unit. The main interpretational point – as manifested in practice – is that the allowed weapons are essentially handguns.Footnote 145 In an interpretation given by some States during the negotiations for the Additional Protocols at the Diplomatic Conference of 1974–77, fragmentation grenades, weapons which cannot fully be handled or fired by a single individual and those intended for non-human targets were excluded.Footnote 146
This provision is based on the experience that in situations of armed conflict, the ordinary police enforcement mechanisms have often crumbled, and that concomitantly, criminality spreads. A medical unit contains materials which can be economically valuable (the coronavirus crisis of 2020 shows how medical material can be sold on black markets).Footnote 147 A medical post must consequently be guarded, and to be efficient, the guards must be armed. However, their armed opposition must be directed only against the criminal elements, not against the military forces of the enemy. The medical unit may not be defended against the enemy belligerent; that would amount to AHTTE.Footnote 148 In view of this finality, the “necessity” requirement explains why only handguns are allowed, as only those guns are necessary to oppose crime; heavier weapons would have a belligerent function and are thus not necessary for the type of allowed defence. However, the question could arise as to whether such heavier weapons could be exceptionally conceded if the marauders display a level or organization and force which requires more than handguns to defend against them. In the absence of a permission under the applicable IHL provisions, the commander of the unit will have to seek an agreement with the enemy forces on this point.
It has been rightly said that arming of medical personnel, especially if civilian (as under Article 13 of AP I), is not without problems.Footnote 149 Such personnel could be mistaken as combatants or as abusing their civilian function. In view of the necessities of defence against crime, however, this shortcoming cannot be wholly avoided. For this reason, it is all the more important that the weapons carried be of a type (i.e., handguns) that immediately allows others to grasp their true purpose.
Articles 13(2)(b) of AP I and 22(2) of GC I regulate that when medical units are under armed protection by guards,Footnote 150 “specifically to the defence of the wounded and sick contained therein”,Footnote 151 this does not constitute AHTTE. Guards include both “medical and non-medical personnel”.Footnote 152 Under exceptional cases,Footnote 153 “non-medical members of the armed forces”Footnote 154 and “civilian uniformed police force”Footnote 155 are also envisaged. Guards are subject to the same conditions as armed medical personnel regarding the type and use of weapons permitted: “only the same type of weapons, notably ‘light-individual weapons’, may be carried and, where necessary, used for defensive purposes only”.Footnote 156
Articles 13(2)(c) of AP I, 22(3) of GC I and 19(2) of GC IV stipulate that the temporary presence of small arms and ammunition found inside the medical unit, which have been taken from the wounded and sick and have not yet been handed over to the proper service (“i.e. authorities outside the medical establishment or unit”Footnote 157), would not constitute AHTTE. The understanding of the arms concerned relates to “portable weapons”Footnote 158 and is broader than the “individual portable weapons”Footnote 159 authorized for medical personnel.Footnote 160 “[S]ome weapons which are slightly heavier than those which are authorized for medical personnel could be involved, such as, for example, small machine guns, provided that they are portable, even if this should require two or three soldiers.”Footnote 161 Conversely, “to store arms or ammunition (other than the temporary storage of arms and ammunition taken from the wounded and sick and not yet handed over to the competent authority)”Footnote 162 in medical units constitutes AHTTE. Moreover, “the presence of any weapons other than portable weapons inside a medical establishment or unit could not be justified even on a temporary basis”.Footnote 163
Articles 13(2)(d) of AP I and 19(2) of GC IV stipulate that the presence of armed forces or other combatants inside the medical unit for medical reasons would not constitute AHTTE. Arguably, a temporary presence of combatants or other military objectives inside the medical unit for non-medical reasons does not automatically constitute AHTTE either.Footnote 164 It cannot be assumed that these persons or objects are using the medical unit for military purposes – e.g., being combatants directing missions from the unit – without ascertaining further facts. The combatants could, however, be attacked as lawful targets, but then all precautions would have to be taken not to interfere with the medical unit. This will in most cases mean that the adverse belligerent will have to wait until these persons have left the unit, since otherwise the collateral damage would be excessive with regard to the military advantage anticipated (AP I, Article 51(5)(b)).
AHTTE versus perfidy
AHTTE may qualify as perfidy, codified in Article 37(1) of AP I, if done in order to kill, injure or capture an enemy combatant.Footnote 165 Consider an ambulance approaching a military checkpoint of the adverse party. The soldiers manning the checkpoint approach it to facilitate its passage, but are fired upon by combatants hiding inside it. This conduct qualifies not only as perfidy but also as AHTTE. Certain forms of AHTTE consequently overlap with perfidy – that is, abuse of the medical services’ special protection in order to gain some military advantage or to deny the adversary such an advantage. The two concepts have similar characteristics: both are deceits characterized by an action contrary to the principle of good faith,Footnote 166 the gist of which consists of a belligerent using obligations under IHL for hostile purposes,Footnote 167 and both undermine compliance with the law.Footnote 168 The difference is that AHTTE do not have to result in the death, injury or capture of an enemy combatant.
AHTTE versus acts of hostility
AHTTE are broader than an “act of hostility” as codified in Article 8(a) of AP I. Harmful acts are acts causing or likely to cause harm, while hostilities refer to acts of warfare – i.e., to military operations. The legal understanding of “harmful”, as previously discussed, “refers not only to direct harm inflicted on the enemy, … but also to any attempts at deliberately hindering his military operations in any way whatsoever”.Footnote 169 “[T]he concept of ‘hostilities’ refers to the (collective) resort by the parties to the conflict to means and methods of injuring the enemy.”Footnote 170 Although the term “act of hostility” does not have a clear definition under IHL, it must be understood by analogy to the term “hostile act” in Articles 41(2)(c) and 42(2) of AP I, with guidance from Article 51(3) of AP IFootnote 171 – i.e., “[h]ostile acts should be understood to be acts which by their nature and purpose are intended to cause actual harm to the personnel and equipment of the armed forces”.Footnote 172 This is manifestly a narrower notion than the one on harmfulness, which encompasses indirect effects on military operations of the adverse party.
AHTTE versus direct participation in hostilities
For the same reason, AHTTE is also a broader concept than that of “direct participation in hostilities” (DPH) contained in Article 51(3) of AP I and Article 13(3) of AP II.Footnote 173 Acts of DPH are precisely linked to “hostilities” and not to “harm”. There are, however, some broad interpretations of DPH – such as by the United States – that end up making the concept of AHTTE a narrower one than DPH. This is particularly true when a hostile intent of an organization, without actual conduct to carry it out, is taken to allow an attack on an individual member of that organization, to whom the overall hostile intent is imputed.Footnote 174 Apart from these peculiar interpretations, it can be said that (1) the required “threshold of harm” for AHTTE is lower than that of DPH, the latter supposing “hostilities”; (2) “direct causation” – i.e., a direct link between AHTTE and the performance of concrete military operations – is not required; and (3) “belligerent nexus” is a prerequisite for both notions, whereby the AHTTE must be specifically designed in support of a party to a conflict or to the detriment of another. This implies that if civilian medical personnel directly participate in hostilities, this would automatically amount to AHTTE. Conversely, if civilian medical personnel commit AHTTE that do not amount to DPH, these persons may lose their special protection; however, they do not lose their general protection, “unless and for such time as they take a direct part in hostilities”.Footnote 175 In other words, a civilian's commission of AHTTE does not automatically render the person liable to direct attack. “This would only be the case if these acts equally qualify as acts of ‘direct participation in hostilities’.”Footnote 176
AHTTE versus military objective
The next question relates to when AHTTE would turn a medical object into a military objective under Article 52(2) of AP I. As is known, the test on whether an object is a military objective depends on two contextual cumulative elements, namely a military contribution and a military advantage. “Contribution” means that an object renders services and has usefulness to the concrete conduct of military operations. The link between the contribution and the military operations must be direct.Footnote 177 Moreover, the contribution must be effective, which implies that it must be real and discernible.Footnote 178 It must be recalled that AHTTE encompass both direct and indirect interferences with military operations;Footnote 179 a direct link of AHTTE with the performance of concrete military operations is not required. This implies that a medical object used to commit AHTTE does not automatically become an object that makes an effective contribution to military action. When it does, AHTTE could extend to its “location, purpose or use” but not to its “nature” aspect under Article 52(2) of AP I, as a medical object does not acquire an intrinsic military character.
As to the second element, the effectiveness of the contribution, would the medical object's destruction, capture or neutralization offer a definite military advantage for the attacking side? “[A]n ‘advantage’ may be defined as everything which facilitates the military operations.”Footnote 180 It must be “military”, must be “definite”, and must exist “in the circumstances ruling at the time”.Footnote 181 The answer is clearly in the negative. Not all objects, including medical objects used to commit AHTTE and/or effectively contributing to military action, would yield a definite military advantage when attacked. “[A] much wider pool of objects [may] be effectively contributing to the defender's military action, but only some of them might offer a real military advantage in concrete circumstances.”Footnote 182 Thus, the overall conclusion of the ICRC seems correct:
It is submitted that not all forms of ‘acts harmful to the enemy’ would make an effective contribution to military action and an attack directed against them would not, in the circumstances ruling at the time, offer a definite military advantage. The failure to fulfil either of these requirements implies that such medical objects may not be considered to have become military objectives.Footnote 183
Conversely, certain AHTTE may lead an object to become a military objective when the two-pronged test under Article 52(2) of AP I is satisfied, e.g. when the location is used to fire on opposing troops. It must be recalled again that committing AHTTE leads to the loss of special protection under the relevant provisions, which includes immunity from attack, but that conducting an attack still requires the attacking party to satisfy Article 52(2).
AHTTE in case of doubt
Based on “humanitarian considerations”,Footnote 184 “in case of doubt as to whether a particular type of conduct amounts to an ‘act harmful to the enemy’, it should not be considered as such”.Footnote 185 This interpretation is in line with the gist of the rules expressed in Articles 50(1) and 52(3) of AP I, with their legal presumptions of the civilian character of a person and of an object under the rules governing the conduct of hostilities. Although similar provisions are not found in AP II for NIAC, “[o]ne cannot automatically attack anyone who might appear dubious”.Footnote 186 These legal presumptions are in favour of the protection of the person and object in question, which leads to the protection of the wounded and sick – the ultimate aim of special protection under IHL.
Consequences of the loss of special protection
The main consequences of the loss of special protection are that the enemy is no longer obliged to refrain from interfering with the work of the medical services or to take positive measures to assist it in its work,Footnote 187 after fulfilment of the warning requirements. Further, if the warning, time limit and non-heeding are fulfilled, the service can be attacked. But there remain open questions, such as: when a person commits AHTTE inside a medical unit, should the response be given to the person only, or can the entire unit be attacked? If only a part of the unit is abused, can the whole unit be attacked? Does the abusive act affect the entire unit's protected status? And to what extent can medical personnel be attacked?
For military medical personnel, the commission of AHTTE does not change their status as medical personnel, just as DPH does not change the status of civilian into combatant.Footnote 188 The only consequence is the loss of special protection (because of AHTTE and the fulfilment of the warning-prong requirements).Footnote 189 In this case, the concerned medical personnel, normally protected against attack, will be liable to attack, exactly like civilians under the DPH doctrine.Footnote 190 It must also be recalled that military medical personnel, either generally or once having lost their special protection, can be targeted at all times,Footnote 191 and are not subjected to a contextual two-pronged test as are objects under Article 52(2) of AP I. If civilian medical personnel engage in AHTTE, these persons analogously remain civilians. They cannot, however, be attacked all the time, since they enjoy general protection under Articles 48 and 51 of AP I, as well as related customary international law; it is only if the AHTTE amount to DPH (i.e., are not merely “harmful” but also “hostile” in the sense discussed above), or if medical personnel engage in DPH in addition to AHTTE, that an attack on them becomes lawful under IHL. Conducts to be discussed under AHTTE in this context include the collecting and communicating of intelligence related or unrelated to combat operations, the shielding of able-bodied combatants, or firing on adverse forces.
In order to determine the loss of special protection of medical objects, both military and civilian, so that they can be attacked, two tests need to be satisfied: an AHTTE test together with the two additional requirements for the loss of special protection (warning, unheeded), and a military objective test under Article 52(2) of AP I for the loss of general protection against direct attacks. In contrast to medical personnel, where the difference in the respective legal status of military medical personnel and civilian medical personnel leads to an additional DPH test for civilian medical personnel in order to assess their loss of protection against direct attack, both military and civilian medical objects have the same civilian status under the rules governing the conduct of hostilities,Footnote 192 and thereby undergo the same two tests (loss of special protection and loss of general protection).
An important question is to what extent single acts or localized action within a medical unit may turn the whole unit into a military objective liable to direct attack. The US Department of Defense Law of War Manual states that “a single enemy rifleman firing from a hospital window would warrant a response against the rifleman only, rather than the destruction of the hospital”.Footnote 193 The legal reasoning has not been made explicit, although mention is made that “[s]uch use of force in self-defense against medical units or facilities must be proportionate”.Footnote 194 Is this because the United States, in this specific case, considers that the military objective test has been narrowed down to the individual and not to the entire unit, as the conduct of the rifleman was not sufficient to transform the unit into a military objective? Or that the military objective test was satisfied for the unit, but the proportionality test was not automatically fulfilled by the same token?
In general terms, it must be said that a medical service cannot be automatically considered as a single military objective. If the military aim of neutralizing the AHTTE can be obtained by attacks on single parts of it, this narrower course must be chosen. This solution flows from the fact that the proportionality principle applies to all protected persons and objects, as well as from the fact that Article 57 of AP I requires precautionary measures in all types of situations.Footnote 195 This nuanced position finds some support in the jurisprudence of the aforementioned ICTY Galić case, which discussed the lawfulness of direct attacks against Koševo Hospital in Sarajevo by a party to the conflict: the Sarajevo Romanija Corps (SRK), a branch of the Army of Republika Srpska.Footnote 196 The hospital had become a dual-use object, an object serving at once civilian and military purposes. While the wounded and sick were being treated, it had also become a “military base”Footnote 197 of the opposing party to the conflict, the Army of Bosnia and Herzegovina (ABiH). Weapons were being fired from its grounds by the ABiH forces against the SRK forces.Footnote 198 The relevant factual findings made by the Trial Chamber, also confirmed by the Appeals Chamber, were that there were attacks from both sides: “the SRK was fired at from the hospital grounds, and … the SRK fired on the hospital grounds and building”.Footnote 199 The Court noted that the hospital “was regularly targeted during the Indictment Period by the SRK”,Footnote 200 that the “ABiH mortar fire originated from the hospital grounds or from its vicinity and that these actions may have provoked SRK counter-fire”.Footnote 201 The Trial Chamber concluded that the SRK firing on the hospital buildings “was certainly not aimed at any possible military target”.Footnote 202 This was subsequently dismissed by the Appeals Chamber as “partially incorrect”:Footnote 203
the Trial Chamber erred in law in determining that fire on the hospital was “not aimed at any possible military target”, because fire from the hospital turned it into a target. At the same time, however, military activity does not permanently turn a protected facility into a legitimate military target. It remains a legitimate military target only as long as it is reasonably necessary for the opposing side to respond to the military activity. Additionally, an attack must be aimed at the military objects in or around the facility, so only weaponry reasonably necessary for that purpose can be used.Footnote 204
Conclusion
As a conclusion, some general recommendations can be presented. There are three points to be made.
First, attacks against hospitals must be viewed only as a last resort. This first recommendation subscribes to the one made as part of the ICRC's Health Care in Danger project:
in consultations with military experts …, a recommendation was made, not necessarily based on legal considerations, that kinetic strikes against a medical facility that has lost protection should be considered a last resort, and that options other than launching a direct attack on such a facility should be contemplated.Footnote 205
Factoring not only the direct effects of the attack but also the reasonably foreseeable long-term and cumulative effects into incidental harm under the proportionality calculus would in most cases outweigh the military advantage anticipated.Footnote 206 This would consequently render an attack against a dual-use hospital that has become a military objective unlawful. In practice, the gist of the initial response to AHTTE is don't attack, provide a warning, and provide a time frame. “[T]he only remedy, practically speaking, available to the aggrieved Party to the conflict would most likely be capture or another appropriate measure of enforcing compliance.”Footnote 207
Second, the notion of military objective and the attack allowed must be framed narrowly in the present context. When an attack against a hospital is deemed prima facie lawful, as long as the hospital is simultaneously and continuously being used for the care of the wounded and sick, it is recommended, to the extent feasible, that the attack is made in a limited form and narrowed down to the exact military objective, as defined under Article 52(2) of AP I or its customary law equivalent,Footnote 208 within the hospital, and not directed at its entirety. “Article 51(4)(a) of Additional Protocol I requires that the attack be directed at the ‘specific’ military objective.”Footnote 209 As much as possible, weapons used for the attack should be those necessary and proportionate to the exact military objectives defined within the military component of the hospital, so as to incapacitate those, and should not be directed against the civilian component or against the entire building.Footnote 210
Third, a prior warning must be considered as a stringent requirement for “authorized” and “unauthorized” hospitals.Footnote 211 The following practical example illuminates the significance of this last recommendation even in atypical situations.
Consider a civilian hospital destroyed and abandoned due to an armed conflict. It no longer functions as a hospital. The medical personnel have left, so have the wounded and sick under their care. The local residents have also fled the area. After many months, new residents arrive, and a non-State armed group takes position in the building, which was once a hospital. Before an adverse belligerent launches an attack against this building, when such an attack is deemed lawful, a warning would arguably still be necessary. It is possible that a civilian seeking medical care could mistakenly enter the structure, for instance, due to the left signboards indicating that the structure is a hospital. How could the adverse belligerent know that the new population is aware that the structure is not a hospital anymore? How could they assume that a civilian, seeking medical treatment, will not enter it?
When, in the extreme, a hospital becomes a military objective and is liable to direct attack, it is recommended that the “warning procedural requirements” under the relevant provisions governing the loss of special protection are expanded to hospitals that do not fall within the meaning of IHL. According to the ICRC's Customary Law Study, “a lot of practice does not expressly require medical units to be recognised and authorised by one of the parties”.Footnote 212 Moreover, under the Rome Statute of the International Criminal Court, the war crime of “[i]ntentionally directing attacks against … hospitals and places where the sick and wounded are collected, provided they are not military objectives”,Footnote 213 is not confined to the IHL definition of authorized medical units. These factors seem to indicate that States, upon recognition that a facility is being used to provide medical care to the wounded and sick, acknowledge the existence of special protection attached to it.Footnote 214 There is no difference between the protective status of the wounded and sick in “authorized” and “unauthorized” hospitals, and thus, it does not make much sense to deprive the latter of the opportunity of being evacuated. Finally, the principle of precaution requires belligerents to do everything feasible to verify that the objectives (persons and objects) are neither civilian nor enjoy special protection but are military objectives.Footnote 215 This further includes ascertaining whether the attack does not violate the principle of proportionality, to which the wounded and sick are also entitled.
