1. Introduction
The need to improve environmental protection in non-international armed conflict has arguably never been greater. Despite the prevalence of non-international armed conflicts in the present dayFootnote 1 causing damage to the environment and high-value natural resourcesFootnote 2 such as oil, gas, timber and minerals, and in areas of environmental significance such as national parks and special areas of conservation, the laws of armed conflict remain dangerously out of touch with the realities of modern conflict. While specific provisions in Additional Protocol I purport to regulate the degree of environmental damage that can be caused in international armed conflict,Footnote 3 no such restrictions apply during non-international armed conflict.Footnote 4 Despite frequent calls for the improvement of the environmental laws of non-international armed conflict,Footnote 5 meaningful progress in this regard has not been made to date.Footnote 6 However, an unprecedented and long overdue opportunity for such reform now exists through the examination of environmental protection in times of armed conflict by the ILC.Footnote 7 Indeed, there may be ‘no other international body with the knowledge, authority and terms of reference to accomplish … [the] … task’Footnote 8 of finally achieving enhanced protection for the environment during armed conflict, and in particular, during non-international armed conflict. This article makes timely and relevant observations about the differences in the way that the customary international law principles of distinction, proportionality and military necessity apply during non-international armed conflict. Should the ILC wish to take advantage of these differences in discussing and developing principles de lege ferenda Footnote 9 on the protection of the environment in non-international armed conflict, conflict circumstances that have long evaded clear and enforceable restrictions on the degree of environmental harm may finally be considered.Footnote 10
Exploring the differences between the applicability of these three key provisions of customary international humanitarian law as between international and non-international armed conflict is important as some scholars have suggested that customary principles can only be interpreted according to the parameters set by treaty-based provisions, even if doing so lowers the degree of environmental protection that could otherwise result.Footnote 11 As non-international armed conflicts are not shackled to the problematic environmental provisions in Additional Protocol I – there are no comparative provisions in Additional Protocol II – the customary principles of distinction, proportionality and military necessity can, and should, be authoritatively interpreted in a way that provides the greatest degree of environmental protection possible in non-international armed conflict. The analysis in this article serves to advance the debate on the legal differences between environmental protection in international and non-international armed conflictFootnote 12 by asserting that the absence of a specific environmental provision in Additional Protocol II could actually be an advantage when exploring ways in which existing provisions could be more purposively interpreted. As states have been reluctant to develop new treaty-based law on this issue, purposively interpreting existing law might be the only feasible way to enhance and improve environmental protection in non-international armed conflict.Footnote 13
The ILC has already considered a number of draft principles related to environmental protection during armed conflict,Footnote 14 but these draft principles appear at present to be extremely conservative statements of existing law which neither explore ways in which customary international law differs as between international and non-international armed conflictFootnote 15 nor the ways in which fresh interpretations of existing rules could significantly enhance environmental protection during non-international armed conflict in particular.Footnote 16 For example, the draft principle that refers collectively to the customary principles discussed in this article simply asserts that ‘[t]he law of armed conflict, including the principles and rules on distinction, proportionality, military necessity and precautions in attack, shall be applied to the natural environment, with a view to its protection’.Footnote 17 Dynamically interpreting customary international law in a way that reflects ‘emerging values cherished by society’Footnote 18 would ensure that the guidelines or principles developed by the ILC do more than merely repeat prior attempts at conveying the law as it stands,Footnote 19 attempts which have been criticized as failing to make meaningful progress towards better environmental protection during armed conflict.Footnote 20 The analysis in this article, therefore, intentionally goes beyond a mere examination of the ways in which the customary principles of distinction, proportionality, and military necessity contribute to environmental protection in non-international armed conflict; it challenges all parties engaged in the ILC’s programme of work to progressively interpret these key customary principles and to include such interpretation in any draft principles that are developed.Footnote 21 In purposively interpreting these customary laws, the trajectory of these laws may be altered ever so slightly, and in time states may take heed of the direction provided so that a new course is charted, one that responds to the exigencies of contemporary armed conflicts, and ultimately converges with global standards of environmental protection.
2. The principle of distinction
The principle of distinction, which states that only military objectives can be legitimately targeted during the conduct of hostilities,Footnote 22 is considered ‘the first test to be applied in warfare’.Footnote 23 Under this principle, civilians and civilian objects can never be the legitimate object of an attack. If the environment is considered to be a civilian object – and scholars have argued strongly for this interpretationFootnote 24 – then it benefits from absolute protection against attack under the principle of distinction, making it unlawful to target the environment directly under any circumstances. However, protection as a civilian object may be lost if the environment, or any part of it, is defined as a military objective.Footnote 25 As a military objective, the environment, or any part of it, would be a legitimate target.Footnote 26 Indeed the extent to which the environment could be classified as a civilian object was the subject of substantial discussion at the ILC.Footnote 27 It is critical that any future consolidated principles developed go beyond merely restating the principle of distinction, but instead address some of the inherent problematic issues associated with the classification of the environment as either civilian or military in nature in non-international armed conflict.
2.1 Classification of the environment under the principle of distinction
As the principle of distinction permits the targeting of military objectives and prohibits the targeting of civilian objects, the environment benefits from protection under this rule when it is considered to be a civilian object. It loses protection under the principle of distinction when it is considered to be a military objective. The former Special Rapporteur to the ILC proposed a draft principle reflecting this application of the law,Footnote 28 though she refrained from defining the environment as a civilian object, instead opting to classify it as being ‘civilian in nature’.Footnote 29 The critical examination below assesses the extent to which the environment is protected by the customary principle of distinction as a civilian object, military objective, and dual-use object. It is argued that any confusion created by the classification of the environment as a civilian object can be overcome with the development of guidance by the ILC to support parties to a non-international armed conflict in assessing the environment correctly under this principle.
2.1.1 Classifying the environment as a civilian object
The laws of armed conflict do not state that the environment is a civilian object per se, but it is commonly understood to be civilian in natureFootnote 30 and the Special Rapporteur to the ILC on the protection of the environment in times of armed conflict has affirmed this prima facie classification.Footnote 31 There is some dispute as to whether the environment as a whole can be classified as civilian, or whether this classification can be applied only to specific objects within the environment.Footnote 32 It would seem that the practice of states and international organizations to date has been to refer to the natural environment as a complete entity rather than distinguishing between parts of the environment in this regard.Footnote 33 Therefore, there is a compelling argument to be made for interpreting the environment as a whole as being civilian in nature, protected in its entirety from direct attack as such. However, whether the environment is interpreted as being wholly civilian or civilian in its entirety through the sum of its parts,Footnote 34 the same conclusion is reached:Footnote 35 the prima facie interpretation of the environment as a civilian object.
Some members of the ILC has previously suggested that the environment as a whole could not be considered civilian in its entirety by default.Footnote 36 Alternative proposals for draft principles in this regard have refrained from classifying the environment as a civilian object, instead asserting that ‘[n]o part of the natural environment may be made the object of an attack, unless and until it becomes a military objective’.Footnote 37 These proposals succeeded in replacing the originally proposed draft principles, which means that there is no explicit acknowledgement that the environment is a civilian object in the ILC’s draft principles as they stand.Footnote 38
However, it is important to note that recognizing the environment as being civilian in nature is not an aberration of the laws of armed conflict and it would not preclude, as some have suggested, the movement of troops from a city to a forested area.Footnote 39 If parts of the area in which armed forces are located conform to the definition of military objectives, then they may be targeted. Explicitly recognizing the default position of all environmental objects as being civilian in nature is significant in terms of shaping perceptions, and it explicitly acknowledges that the targeting of environmental objects is a deliberate exception rather than a thoughtless consequence of military action during armed conflict. One of the major issues that has plagued the laws of armed conflict and their failure to adequately prohibit certain types of environmental damage in non-international armed conflict is the absence of an explicit recognition that the environment is entitled to protection. Recognizing the environment as being civilian in nature is important in this regard, and also for the purposes of assessing proportionate collateral damage. If it is not explicitly acknowledged that the environment as a whole is entitled to protection against direct attack as a civilian object, then calculating what amounts to proportionate or disproportionate damage may be seriously affected.
Given this conclusion, it is a much more straightforward statement of the law to acknowledge the prima facie civilian status of the environment, as that would clearly establish the requirement for parties to a non-international armed conflict to refrain from attacking environmental objects without consideration, and it would affirm the requirement to evaluate specific environmental objects against the definition of military objectives if they are to be the object of an attack. Acknowledging the civilian status of the natural environment would compel parties to a non-international armed conflict to ensure that all parts of the environment directly targeted clearly conform to the definition of military objectives. There have been some positive discussions on this point at the ILC, and it would certainly be a useful clarification of the law if the Commission decided to revisit their proposed draft principles and provide determinative guidance in this regard.Footnote 40
Recognizing, as the Special Rapporteur to the ILC has done,Footnote 41 that the environment is neither a non-object, nor a benign venue in which conflict takes place, means that the environment in general, as well as parts thereof, would benefit from the greatest possible protection under the principle of distinction. Any draft principle that fails to acknowledge the civilian status of the environment risks creating the impression that the environment is not protected against direct attack, a potentially regressive step which might send a message to parties engaged in non-international armed conflict that the environment is ‘a valueless part of the scenery in which a battle takes place’.Footnote 42 Any future principles that are developed should, therefore, not merely affirm the applicability of the principle of distinction when targeting environmental objects, but should clearly state that the environment as a whole is presumed to be a civilian object as this would create clear instructions for belligerents during the conduct of hostilities in non-international armed conflict.
A further justification for classifying the environment as a whole as being civilian in nature would be to remove any confusion regarding the concurrent application of customary and treaty-based law during non-international armed conflict. While elements of the environment are protected through Article 14 of Additional Protocol II,Footnote 43 for example, environmental protection as a whole is stronger in non-international armed conflict under the customary principle of distinction. Article 14 limits protection to those objects which, if targeted and destroyed, would cause starvation amongst the civilian population. There is no such qualification or limitation attached to the protection afforded to civilian objects under the customary principle of distinction. In the absence of a clear statement acknowledging the classification of the environnment as a civilian object, belligerents in non-international armed conflict may prefer to adhere to the treaty-based provision as it shields fewer environmental objects from direct attack. Defining the environment as a whole as civilian in nature, and affirming the concurrent and compulsory application of the customary principle of distinction, would reduce the risk that only specific environmental objects essential to the survival of the civilian population would be viewed as protected objects during the conduct of hostilities. While a principle on the relationship between the principle of distinction and the environment has been proposed to the ILC,Footnote 44 it could go much further towards clarifying the applicable law to enhance environmental protection in non-international armed conflict.
2.1.2 Classifying the environment as a military objective
Military objectives generally include objects that contribute to ‘the enemy’s war-fighting or war-sustaining capability’Footnote 45 and it is not difficult to imagine a multitude of circumstances in which the environment could be viewed as such during non-international armed conflict: from fuelling and funding the conflict, to providing camouflage and sustenance, it is very difficult to completely divorce armed conflict from its surrounding environment. Under the principle of distinction, the environment can lose its protection as a civilian object only if by reason of its ‘nature, location, purpose’Footnote 46 it makes an ‘effective contribution to military action’,Footnote 47 and if its ‘partial or total destruction, capture or neutralization, in the circumstances ruling at the time, offers a definite military advantage’.Footnote 48 To the extent that the natural environment satisfies these criteria, it is no longer considered to be a civilian object, but instead a military objective which can be lawfully targeted during the conduct of hostilities. The International Committee of the Red Cross (ICRC) recognizes that the definition of military objectives is ‘a wide one, which includes areas of land, objects screening other military objectives and war-supporting economic facilities’.Footnote 49 While elements of the environment do not automatically or intrinsically conform to the definition of military objectives, their use by parties to an armed conflict means that they can become legitimate targets.Footnote 50 Therefore classifying the environment as a military objective is not, in many circumstances, a conceptual stretch of the imagination.
In the context of contemporary non-international armed conflicts which have a particularly strong connection to the exploitation of natural resources, determining the extent to which the environment, or elements of it, satisfy the definition for military objectives, is a pressing issue which needs to be addressed in any principles that are developed to enhance environmental protection in these circumstances. Natural resources – valuable, precious and vulnerable as they are – may be so closely connected to the conflict that classifying them as military objectives may not be a challenging exercise. Although objects need to make a contribution to military action to be classified as a military objective, such that attacking them will result in military advantage,Footnote 51 in many non-international armed conflicts that involve natural resource exploitation, the lines between contributing to military action and contributing merely to the ‘war-sustaining capability’Footnote 52 of a party engaged in the armed conflict will be blurred. It has been argued that revenue-generating natural resources which are exploited by an armed group to support their engagement in a conflict do not make a sufficiently direct and effective contribution to military action,Footnote 53 however, the contrary could certainly be argued with equal legal weight. For example, if a non-state armed group took control of an oil refinery, and if the profits from the sale of that oil are the only source of funding supporting the group’s conflict effort, then targeting that refinery could result in a definite military advantage. The fact that there is an arguable point in this regard means that environmental objects may be too easily classified as military objectives,Footnote 54 and the protection against attack that they benefit from as civilian objects decreases significantly as a result.
Examples of the way in which environmental objects can be construed as military objectives abound throughout the history of non-international armed conflict. During the American Civil War, for instance, the destruction of cotton fields was not considered to be a breach of the principle of distinction: cotton was the Confederacy’s primary export at the time, the sale of which funded the purchase of Confederate supplies and weapons, and so it was considered to be a military objective which could be lawfully targeted on that basis.Footnote 55 Similar issues arise frequently in contemporary non-international armed conflicts: the exploitation of natural resources has been recognized by the UN Security Council as a major factor in funding and perpetuating armed conflict in the Central African RepublicFootnote 56 and as a result such resources may be classified as military objectives that can be directly and legitimately attacked during the conduct of hostilities.Footnote 57 It is argued here that any principles that are developed by the ILC could compel parties to an armed conflict to construe the definition of military objectives as narrowly as possible when it comes to environmental objects, particularly elements of the environment that are at risk of additional harm through exploitation as a result of the conflict.
There is a danger that classifying the environment as a whole as a civilian object might encourage belligerents to use civilian environmental objects as shields against attack, much in the same way that human shields are used.Footnote 58 However, unlike the law relating to human shields,Footnote 59 the use of civilian environmental objects as a shield against attack would merely result in those objects being reclassified as military objectives which could be legitimately targeted.Footnote 60 In contemporary non-international armed conflict, ‘[i]nsurgents often use tropical forests as home bases and hiding grounds; counter-insurgency forces often respond by slashing and burning forests and by polluting rivers, viewing both as legitimate theatres of operations’.Footnote 61 These kinds of actions undermine the protection that the environment, in particular valuable or vulnerable environmental locations, needs to benefit from during non-international armed conflict. If military targets are deliberately located in special areas of protection or conservation, for example, the nature of the surrounding environment may change from civilian to military, thereby removing the absolute protection against attack that would otherwise apply to civilian objects through the principle of distinction. The ILC should retain draft principles already proposed in this regardFootnote 62 making the use of valuable or vulnerable environmental civilian objects by belligerents in non-international armed conflict a breach of the principle of distinction, much in the same way that the use of human shields is prohibited.
2.1.3 Classifying the environment as a dual-use object
It is ‘beyond dispute’Footnote 63 that those engaged in non-international armed conflict are required to make the primary distinction between civilians and civilian objects on the one hand, and military objectives on the other, before embarking upon any method or means of warfare likely to result in harm.Footnote 64 The law indicates clearly that objects can only have a single status at any given time, either civilian or military, never both concurrently. Yet the natural environment will most often serve both military and civilian uses simultaneously, and this makes the determination of the civilian or military status of environmental objects one of the most difficult applications of the principle of distinction in contemporary non-international armed conflict.
As a dual-use object, strictly separating the areas or times of civilian use from military use when applying the principle of distinction on the battlefield in non-international armed conflict could prove extremely problematic.Footnote 65 The ICRC has concluded, from a review of state practice and opinio juris, that the law is not clear on what to do where there is doubt as to an object’s civilian or military status.Footnote 66 While there is some, albeit inadequate, guidance in the treaty-based laws of international armed conflict, no such provisions exist that apply during non-international armed conflict.Footnote 67 As a dual-use object, therefore, the environment is at risk of significant harm.
The ILC is in a strong position to propose principles that clarify the lawFootnote 68 and provide guidance to belligerents in order to improve environmental protection in non-international armed conflict. Such guidance could take many forms: for example, the ILC could suggest that special areas of conservation, including areas that contribute to the solution of global problems such as climate change, food security, or water security, and areas of cultural significance, should always be considered civilian objects.Footnote 69 This would remove any element of subjective judgement where such areas were concerned.Footnote 70 If complemented by a principle which makes using irrefutably civilian environmental objects as shields against attack a breach of the principle of distinction, greater protection would be achieved for particularly important and vulnerable environmental locations than currently exists under the customary laws of armed conflict, and that enhanced protection would be directed to parts of the environment that perhaps could be argued need protecting the most.
2.2 Indiscriminate attacks
The principle of distinction is sometimes referred to as the principle of discrimination. In this regard, the International Criminal Tribunal for the former Yugoslavia (ICTY) has held that ‘attacks, even when they are directed against legitimate military targets, are unlawful if conducted using indiscriminate means or methods of warfare, or in such a way as to cause indiscriminate damage to civilians’Footnote 71 or civilian objects. In other words, belligerents should not use methods or means of warfare that cannot distinguish between military objectives and civilian objects, and this includes environmental civilian objects. The prohibition against indiscriminate attacks applies as a matter of custom in non-international armed conflictFootnote 72 and the application of this prohibition to environmental civilian objects could be emphasized in any future principles that are developed by the international community, as at present it does not feature in the draft principles that are under consideration at the ILC.Footnote 73
2.3 Conclusion to the principle of distinction
The principle of distinction prohibits damage to the environment in non-international armed conflict when the environment is classified as a civilian object. It does not prohibit damage when the environment is classified as a military objective. Suggestions to strengthen the way in which the principle of distinction can better protect the environment have previously been made and they assert, in relation to the ICRC’s Customary Law Study, that the customary rule should state that ‘[t]he natural environment may not be attacked, unless it is a military objective and only to the extent that it is a military objective’.Footnote 74 While such suggestions echo the present draft principles that have been proposed by the ILC, and are without question a helpful starting point, the real difficulties in applying the principle of distinction to enhance environmental protection relate to determining the civilian or military status of the environment. that is not always a straightforward or simple exercise. Given the strong connection between the environment, natural resources, and contemporary non-international armed conflict, a more detailed examination of the way in which the environment changes from civilian to military classification during these circumstances is fully warranted. Where the environment is considered to be a dual-use object, it is at risk of significant harm, and there should be a presumption in favour of recognizing the environment, or certain elements of it, as being irrefutably civilian in nature to protect particularly vulnerable or important parts of the environment from direct and indiscriminate harm during non-international armed conflict. Principles developed by the ILC could also usefully emphasize the prohibition against indiscriminate attacks to give belligerent parties a clear, accurate, and complete statement of the law.
3. The principle of proportionality
The customary principle of proportionality is another foundational concept within the laws of armed conflict,Footnote 75 and it was referred to in draft principles proposed by the Special Rapporteur to the ILC.Footnote 76 Proportionality recognizes that there is a balance to be struck between the value of a military objective and the incidental damage caused in launching an attack upon that objective.Footnote 77 In striking the balance between proportionate use of force and proportionate collateral damage, the International Court of Justice has stated that ‘[r]espect for the environment is one of the elements that go to assessing whether an action is in conformity with the principles of necessity and proportionality’.Footnote 78 The ICRC has found evidence of state practice and opinio juris which prohibits disproportionate environmental damage when attacks are launched against military objectives during non-international armed conflict.Footnote 79 As such, there is strong evidence to support the assertion that belligerents are legally required to take damage to environmental civilian objects into account when planning proportionate attacks in non-international armed conflict.Footnote 80 The ILC is presently considering a draft principle which suggests that proportionality should be applied to achieve the strongest possible protection,Footnote 81 but there are many interpretive issues which prevent this goal from being realized in any given conflict. Indeed, the argument that ‘little law exists to explain how this should operate in practice’Footnote 82 remains valid. The ILC could develop ambitious interpretations of the principle which both affirm its application to environmental collateral damage and address the issues that presently inhibit the full extent of the environmental protection that can be achieved through better proportionality assessments.Footnote 83
The principle of proportionality requires inadvertent harm to civilians and civilian objects to be balanced against the advantage anticipated by attacking a military objective.Footnote 84 For example, if a military objective is located in an environment which is presumed to be a prima facie civilian object, then although the environment cannot be directly targeted, a certain degree of collateral damage is permitted when the military objective is attacked – the principle of proportionality regulates the extent of the damage that can be considered lawful in those circumstances.
To respect the principle of proportionality belligerents are required to weigh the military advantage that they anticipate to gain from an attack against the expected damage that will be caused as a result. The Office of the Prosecutor at the ICTY observed that ‘military objectives should not be targeted if the attack is likely to cause collateral environmental damage which would be excessive in relation to the direct military advantage which the attack would be expected to produce’.Footnote 85 Illustrating this rule, the United Nations Environment Programme assert that the destruction of ‘an entire village or burning an entire forest to reach a single minor target’Footnote 86 would not be proportionate collateral damage when weighed against the military advantaged gained by the attack. The evaluation of permissible levels of collateral damaged is based on both the direct military advantageFootnote 87 expected from the attack and the value of the environmental civilian object. The greater the value of the military objective, the greater the extent of the proportionate collateral damage that can be caused; the higher the value of the environmental civilian object, the lesser the collateral damage that may be permitted.Footnote 88
3.1 Valuing the environment correctly in proportionality assessments
There is an inherent vagueness within the principle of proportionality that makes calculating proportionate environment damage ‘easier to proclaim than to implement in practice’.Footnote 89 It is not immediately clear from the principle how exactly military targets or environmental civilian objects ought to be valued when assessing the anticipated proportionality of an attack.Footnote 90 Moreover, value judgements may change over time.Footnote 91 The optimum way to conduct a balancing exercise under the principle of proportionality is to compare like values with like.Footnote 92 However, this is not always possible when military objectives and environmental civilian objects are being comparedFootnote 93 since ‘military, humanitarian and environmental values’Footnote 94 are different from each other and not directly comparable.Footnote 95 For example, would attacking enemy headquarters to end a conflict justify the destruction of an endangered species whose extinction is all but guaranteed through the collateral damage expected as a result of the attack? What if the environmental value was more abstract – for example, the benefit of upholding ecosystem integrity – how could that be weighed accurately against the same military objective? There is certainly substantial dissonance between military and environmental valuesFootnote 96 that has notbeen fully reconciled in theory or practice to date.
Valuing the environment correctly and objectively is a difficult task, even without the concurrent requirement to value a military objective, and it is likely an element of the proportionality calculation that state armed forces and non-state armed groups alike are ill-equipped to carry out competently during non-international armed conflict. While in best case scenarios environmental impact assessments may be conducted during the planning phases of an attack,Footnote 97 anticipating the environmental consequences and then valuing those consequences appropriately against military values are very different exercises. Guidance in this regard from the ILC to establish some common ground upon which environment–military valuations can be compared and balanced would, therefore, significantly enhance environmental protection through the principle of proportionality. The breadth of the ILC’s work on the issue of environmental protection in armed conflict,Footnote 98 drawing upon pre- and post-conflict laws as well as the jus in bello, means that methods of valuing the environment that have been developed in other fields of practice could be identified and adapted to develop guiding principles. At the very least, the ILC could recognize the issue and encourage further work to be done on the valuation of environmental objects during non-international armed conflict.Footnote 99
As it stands, there is no method that can be applied to accurately value the environment in proportionality assessments. In reviewing NATO’s bombing campaign against the Federal Republic of Yugoslavia, the ICTY were unable to place a value on the environment that was damaged, asserting instead that at ‘a minimum, actions resulting in massive environmental destruction, especially where they do not serve a clear and important military purpose, would be questionable’.Footnote 100 The ICTY stated that serious environmental damage could only be justified where a ‘very substantial military advantage’Footnote 101 was achieved. However, devoid of value, it would be impossible to determine whether environmental damage is significant or not. For example, would massive environmental destruction amount to the destruction of an entire rainforest ecosystem? What if the last female white rhino became collateral damage in an attack that significantly destabilized enemy forces, shortening the conflict? Would this environmental damage be proportionate to the military advantage gained? The answers depend on how the environment is valued in any given circumstance and principles based on existing international environmental law, or even the dictates of the public conscience, could be developed by the ILC to assist belligerents in making accurate proportionality assessments prior to attack.
3.2 Introducing objectivity into proportionality assessments of environmental collateral damage
The extent of the collateral damage that can be lawfully caused to the environment currently depends on how it is valued subjectively by belligerents.Footnote 102 Military commanders would not, in general, be considered to be environmental experts with the ability to calculate the true value of an environmental object, and as such, the environment is at risk of being under-valued when proportionality calculations are made. If a subjective point of view is presently determinative when calculating proportionality, then there is currently no incentive for commanders to improve their capacity to value environmental targets. Valuing the environment correctly when calculating proportionality may reduce the options available to the commander when planning attacks. Subjective ignorance of the true value of the environment could actually be militarily advantageous under the principle of proportionality as it is currently interpreted. This under-valuation results in greater collateral damage being allowed than would otherwise be lawful under a more objective or informed calculation.
Moreover, there are certainly unresolved issues regarding the foreseeability of environmental damage in pre-attack proportionality assessments. If environmental damage is unforeseeable then of course it cannot be factored into any test for proportionality that is applied in a given situation. However, foreseeability increases with knowledge and knowledge about the environment, the effect of harm on certain parts of the environment, and the inter-connectedness between ecosystems is improving at a significant rate.Footnote 103 It may be argued that the subjective latitude afforded to commanders on the battlefield is naturally diminishing with increasing global knowledge about the environment and the detrimental effects of certain types of harm. Therefore, in developing guidelines to enhance the protection of the environment in non-international armed conflict, the ILC could usefully consider introducing an objective test for the calculation of proportionality where environmental collateral damage is expected,Footnote 104 based not on the subjective knowledge of the specific commander, but the knowledge that a reasonably informed and environmentally-aware commander ought to possess.
While the United Nations Environment Programme claim that ‘[m]any instances of environmental damage could be seen as a “disproportionate” response to a perceived threat and therefore considered illegal’,Footnote 105 this perspective fails to recognize the wholly subjective test that may be applied to evaluate proportionality after an attack has occurred. If the evaluation is based on the subjective knowledge of a specific commander, and if they did not place a high value on the environment in the first place, it is likely that most environmental damage in non-international armed conflict would not be considered disproportionate. Developing principles that insist on a relevant objective test, a test which requires commanders to inform themselves of the types of environmental damage that can occur following certain types of military actions, could incentivize commanders to make proportionality assessments that value the environment appropriately, and could greatly increase the degree of protection that can be expected through the principle of proportionality going forward.
3.3 Conclusion to the principle of proportionality
The principle of proportionality does, indeed, have the capacity to prevent disproportionate environmental damage in non-international armed conflict from occurring. However, belligerents may find it difficult to value environmental objects appropriately, and then compare that valuation against the advantage to be gained from attacking a specific military objective. Moreover, the degree to which environmental damage is considered to be disproportionate currently depends on the subjective value that is placed on the environment by the specific military commander at the time of an attack. This subjectivity is the Achilles heel of the principle of proportionality as many military commanders may not be equipped with the knowledge to enable them to value the environment appropriately, nor are they incentivized to improve their capacity to do so. Insisting that an objective test is used when environmental collateral damage is being evaluated, so that environmental values are properly balanced against anticipated military advantage, would significantly improve the power of the principle of proportionality to protect the environment in non-international armed conflict.
4. The doctrine of military necessity
The doctrine of military necessity is one of the oldest customary principles in the laws of armed conflictFootnote 106 and it manifests itself on the battlefield in two ways. Both have implications for the protection of the environment in non-international armed conflict. Firstly, the doctrine requires all acts on the battlefield to be militarily necessary. This means that any damage that is caused to the environment during armed conflict should not be wanton or excessive because to do so would not serve any military purpose.Footnote 107 Secondly, the doctrine permits, in very limited circumstances, the temporary suspension of specific prohibitions within the laws of armed conflict where a military necessity exists.Footnote 108 Although this would appear to permit environmental damage in situations where a military necessity prevails, in practice the laws of armed conflict do not support this manifestation of the doctrine in non-international armed conflict. However, there appeared to be some uncertainty about the way in which the doctrine of military necessity operated during discussions at the ILCFootnote 109 and so clarification is certainly warranted.
Overall, the doctrine of military necessity, if applied strictly and objectively, can play an important role in protecting the environment during non-international armed conflict. However, critically, the ILC has not engaged in sufficient substantive consideration of military necessity to date.Footnote 110 The following critical analysis may be useful in developing more ambitious and appropriate principles before their current programme of work is concluded.
4.1 Requirement for acts to be militarily necessary
In the first instance, the doctrine of military necessity requires all actions taken during armed conflict to be militarily necessary because damage ‘caused carelessly [is] not “necessary” to the achievement of any military purpose’.Footnote 111 O’ Brien argues that the purpose of military necessity means that there exists ‘no equally effective lawful military means, involving less damage or suffering’Footnote 112 to achieve the same ends. The necessity does not need to be urgent or imperative,Footnote 113 but it must be supported by circumstances which preclude the pursuit of reasonable alternatives at the time the action is taken.Footnote 114 Therefore any environmental damage that occurs during non-international armed conflict must not be wanton or careless, but a consequence of the only reasonable actions that could have been pursued at the time the damage occurred. Damage or destruction to the environment in non-international armed conflict must be connected to the pursuit of defeating enemy forces – it cannot be superfluous.Footnote 115 In this way, the contemporary purpose of military necessity has departed significantly from its origins as a rule to trump humanitarian laws which might otherwise prohibit certain conduct.Footnote 116 This is an important point, with provenance in jurisprudence from the IMT at Nuremberg,Footnote 117 and certainly worth emphasizing in any principles that are developed by the ILC as interpretations to the contrary have begun to emerge in state military manuals.Footnote 118
Military necessity was used to justify environmental damage caused during the Second World War in the The Hostages Trial Footnote 119 at the International Military Tribunal at Nuremberg. In this case, General Lothar Rendulic argued that the scorched earth policy implemented during the German retreat from Finnmark was required by military necessities that existed at the time. The Tribunal held that although the necessity in retrospect did not exist, and viewed with hindsight the damage caused was indeed superfluous, there was sufficient subjective necessity at the time of the actions, even though General Rendulic was mistaken in believing that his forces were in jeopardy of imminent attack, to justify the environmental damage.Footnote 120
The subjective perspective of the commander at the time the destruction occurs continues to be determinative of whether environmental damage is justified by military necessity or superfluous, as the Office of the Prosecutor at the ICTY endorsed it as a legitimate precedent for any similar future case.Footnote 121 Yet the subjective test significantly decreases the positive effect that military necessity can have in prohibiting unnecessary environmental damage during non-international armed conflict since mistaken beliefs, if reasonably and honestly held, would be enough to satisfy the requirements of the doctrine in relation to most environmental damage resulting from a course of action during armed conflict. To improve environmental protection under this application of the doctrine of military necessity, any principles that are developed should challenge this perspective. Furthermore, an objective test must be used to ensure that environmental damage in non-international armed conflict is clearly militarily necessary and not superfluous or wanton.
4.2 Suspension of the laws of armed conflict due to military necessity
During the American Civil War, it was felt that military necessity had the potential to become a ‘rule-swallowing’ norm and so the doctrine was, at the time, very narrowly construed.Footnote 122 However fears about the doctrine subverting the laws of armed conflict were borne out in mid-nineteenth century Germany when the doctrine became the ‘bete noir’Footnote 123 of international law under the maxim Kriegsraison geht vor Kriegsmanier – the necessities of war take precedence over the rules of war.Footnote 124 This interpretation of military necessity permitted ‘the commander on the battlefield [to] decide in every case whether the rules will be respected or ignored, depending on the demands of the military situation at the time’.Footnote 125 The International Military Tribunal at Nuremberg, condemned the kriegsraison theory of military necessity during The Hostages Trial Footnote 126 when they indicated quite clearly that ‘military necessity or expediency [does] not justify a violation of positive rules’.Footnote 127 Military necessity now remains subordinate to the laws of armed conflict at all times.Footnote 128 Fears that military necessity permits ‘uncontrolled brute force to rage rampant over the battlefield or wherever the military have control’Footnote 129 are no longer supported by contemporary interpretations of the laws of armed conflict. Despite the perception that military necessity sometimes appears to justify ‘acts of dubious legality, normality, and utility’,Footnote 130 the doctrine remains fundamentally subject to the laws of armed conflict, rather than as a blanket exception to them.Footnote 131 Arguments in favour of this interpretation refer to the fact that contemporary laws of armed conflict were drafted with the exigencies of military necessity in mind, and provision was explicitly provided for military necessity in relation to some limited treaty-based laws of armed conflict, and not provided in relation to the vast majority of others.Footnote 132
For example, Article 54(5) of Additional Protocol I permits derogation from the prohibition against targeting objects indispensable to the survival of the civilian population in international armed conflict ‘where required by imperative military necessity’.Footnote 133 However, the comparable provision in Additional Protocol II, which applies to non-international armed conflict, contains no such permission to derogate. Therefore, even where a compelling military necessity exists, the protection granted by Article 14 of Additional Protocol II is absolute. The prohibition against pillage in Article 4(2)(g) of Additional Protocol II provides another good example of this point. This provision is frequently raised as a means of prohibiting wanton damage to and looting of natural resources during the conduct of hostilities.Footnote 134 Article 4(2)(g) contains no clause which carves out an exception for situations of military necessity and as such, military necessity could not be used to justify pillage of natural resources in non-international armed conflict. Indeed, no treaty-based provisions that are relevant to environmental protection in non-international armed conflict contain clauses which permit derogations required by military necessity.Footnote 135 It is quite clear that military necessary could not be used to justify environmental damage in non-international armed conflict if such damage otherwise breached existing treaty-based or customary laws of armed conflict.
However, worryingly, the ICRC has concluded, on the basis of state practice and opinio juris drawn from a very small number of statesFootnote 136 that customary international law permits the destruction of the environment in non-international armed conflict if justified by military necessity.Footnote 137 The ICRC has suggested that ‘destruction of any part of the natural environment is prohibited, unless required by imperative military necessity’.Footnote 138 Although this is fundamentally at odds with a correct application of the law, left unaddressed it may in time reverse the subordinate position of military necessity and reinstate a kriegsraison-style norm as the dominant rule. The law is clear at present: military necessity cannot be used to justify a violation of the laws of armed conflict unless it is ‘explicitly provided for by the rule in question’.Footnote 139 The ILC should unequivocally affirm the subordinate status of the doctrine of military necessity in any principles that are developed to ensure that any environmental protection that indirectly results from the treaty-based or customary laws of non-international armed conflict is not undermined.
4.3 Conclusion to military necessity
It is clear that military necessity may only be used to justify a breach of the laws of armed conflict if such an exception is explicitly included in the text of a particular treaty provision or is inherently part of a customary rule. As Hulme surmises, ‘the doctrine of military necessity has become a limited one, active only where sanctioned within the law itself’.Footnote 140 In this regard military necessity does not undermine existing treaty or customary law that provides indirect protection to the environment in non-international armed conflict as the treaty-based rules in Common Article 3 and Additional Protocol II have no associated military necessity clause, and the principles of distinction and proportionality cannot be suspended if an overriding military necessity exists. However, the subjective test for military necessity that is used to assess general environmental damage that occurs on the battlefield weakens the overall level of protection that this customary principle can deliver and there is an imperative need to introduce some degree of objectivity into applications of the doctrine of military necessity going forward.
5. Conclusion
The main objective of this article was to fill key knowledge gaps regarding the protection of the environment in non-international armed conflict through customary international law and in so doing, highlight crucial issues that the international community has an unprecedented opportunity to address as part of the ILC’s ongoing work. The approach to enhancing environmental protection in non-international armed conflict presented in this article – avoiding insurmountable issues regarding the development of new law by progressively and purposively interpreting existing law – has significant potential. It is hoped that the proposals that have been suggested in the analysis above can provide grounds for discussions at the ILC to develop more detailed principles and guidelines which meaningfully improve environmental protection in non-international armed conflict going forward.
In this article, it was demonstrated that the established customary international law principles of distinction, proportionality, and military necessity can each play a better role in enhancing protection of the environment during non-international armed conflict. Progressive interpretations of each customary law, if developed and incorporated into principles by the ILC, would constitute a significant advancement in the legal protection of the environment during non-international armed conflict.
Regarding the principle of distinction, it was argued that a mere restatement of the principle is unlikely to improve environmental protection in future non-international armed conflicts. Instead, clarification that the environment as a whole might be considered a civilian object which cannot be directly attacked, and narrowly construing the circumstances in which the environment can be classified as a military objective, would serve to better improve environmental protection under this principle. While dual-use objects present particularly difficult issues, asserting that some specific environmental objects – those that are of special significance or which contribute to the solution of global challenges – can never be classified as military objectives would enhance environmental protection in non-international armed conflict where it is arguably needed most.
While the principle of proportionality appears to require a straightforward balance between the value of attacking a military objective and the expected resulting collateral damage to civilians and civilian objects, it was argued that valuing environmental civilian objects correctly is not always achieved when this principle is applied in practice. This is due to the inherent subjectivity within the principle, which regards a commander’s subjective valuation of civilian environmental objects as definitive. As a result, environmental civilian objects are frequently under-valued, and therefore at risk of greater collateral damage when attacks are being planned and implemented. This article proposes that the subjective valuation of environmental civilian objects be replaced by an understanding which requires objective valuations of the environment to be factored into proportionality assessments. This would allow a more appropriate value to be assigned to environmental civilian objects, thereby decreasing the risk of undervaluation and the objectively disproportionate harm that can follow. Such an understanding would ensure that any collateral damage that is caused to the environment is minimized as far as possible under the circumstances, which the entire purpose of the principle of proportionality.
It was asserted that the doctrine of military necessity can play a significant role in protecting the environment in non-international armed conflict. It requires all actions taken during armed conflict and all damage to be militarily necessary, and so if damage to the environment is not militarily necessary under the circumstances, then it is not permitted. However, at present, a subjective test is used to assess necessity on the battlefield, and it was argued that this ought to be replaced by an objective test when it comes to determining that environmental damage is militarily necessary. Moreover, while the doctrine of military necessity may permit derogations from specific laws of armed conflict, none of the laws of armed conflict that apply during non-international armed conflict to indirectly protect the environment contain such an exception. Acknowledging this in any development of the law that follows the ILC’s examination of the issue would provide much-needed clarity and improved environmental protection in the battlefield.
While the customary international laws of distinction, proportionality and necessity can be harnessed to deliver better environmental protection in non-international armed conflict, that enhanced protection will only take place if the parameters and the potential of these customary rules are fully and strategically embraced by states and the wider international community. The ILC’s programme of work on environmental protection in armed conflict is an ideal place to begin such ground-breaking changes in the way the law is interpreted and applied, and for novel interpretations of existing law to be shaped. While the draft principles that are presently under consideration by the ILC do little more than refer to existing law, and as such do little to enhance environmental protection, this article demonstrates that there is significant potential for more ambitious proposals to be made to enhance environmental protection in non-international armed conflict going forward.
