International environmental law

International society only came to speak of the disciplines of international environmental law and environmental law on the domestic level after the conceptualization of ‘environment’, principally in the 1960s. However, while international and domestic environmental law have witnessed considerable development since this time, this does not mean to say that their rules and principles do not have their origin in earlier sources. Indeed, there is evidence of laws to protect the environment in even some of the most ancient civilizations. The Mesopotamian state of Ur, for example, declared laws against deforestation around 2700 bc, and the Indian King Ashoka enacted, around 250 bc, a law for the protection of various animal species. Then, in the early industrial period, legal action started being taken against environmental damage. As early as 1739, Benjamin Franklin petitioned the Pennsylvania Assembly to act against the tanneries of Philadelphia for the local pollution they were causing. By the mid-nineteenth century, courts of the world's first country to industrialize on a grand scale, Great Britain, were receiving numerous claims for damage suffered as a result of progressively larger-scale and more intensive industrial processes. In the absence of any notion of ‘environment’ at that stage, these problems were dealt with on the basis of existing common law torts and rules of nuisance, trespass to goods, the enjoyment of property and the action of scentier, which has its unlikely origin in the harm caused to another by a defendant's dangerous animal.

In England, a general notion that each subject of the law is free to do as he or she wishes in his or her own territory, but will be responsible and required to pay compensation if his or her activity results in damage to someone else or someone else's property, has been applied at least since the famous 1868 case of Rylands v. Fletcher, in which this general principle was crystallized and applied to the actions of a farmer who, in filling up his dam before closing off some disused mine shafts, managed to flood his neighbour's interconnected mines.Footnote ²¹ The domestic law systems of other countries that industrialized through the nineteenth century also had damage liability provisions capable of dealing with what were increasingly prevalent instances of environmental damage. For example, the Prussian General Land Law of 1794 had provisions to support the clearly stated principle that ‘whoever impedes another's exercise of his rights, offends him and is responsible for all damage and detriment arising from this’,Footnote ²² a position later written into the German civil law (Bundesgesetzbuch).Footnote ²³ In the United States, the Latin maxim, sic utere tuo ut alienum non laedas (one must so use his own as not to do injury to another), any Roman origins of which are more than questionable,Footnote ²⁴ was frequently invoked in what would be now called environmental damage cases as a derivation from, and legal equivalent of, Christianity's golden rule.Footnote ²⁵

When industry reached a sufficiently large scale to have transboundary environmental impacts, the law of environmental damage stepped onto the terrain of international law. Yet it was not in any public international law, nor specifically environmental context, that the first key cases of transboundary environmental damage were decided. The ground-breaking Trail Smelter arbitration of 1938–1941, generally regarded as the first international environmental law case and the key judicial contribution to international law on liability for loss or damage,Footnote ²⁶ was in fact decided against the background of domestic law on the compensation for damage to another's property described above. The dispute between Canada and the United States (US) centred on the emissions from an enormous zinc and lead smelter in southern British Columbia, the fumes of which damaged farms, orchards, and timberlands more than seven miles across the border in the US state of Washington. Crucially, the agreement between the United States and Canada establishing the arbitral tribunal permitted it to apply not only ‘international law and practice’ but also ‘the law and practice followed in dealing with cognate questions in the United States of America’.Footnote ²⁷ Noting the absence of any sufficient international law on the matter, the arbitral tribunal in fact applied liability principles from US tort law in support of its finding that Canada was responsible for the transboundary environmental damage caused by the smelter and would be required to pay reparations to compensate for that damage.Footnote ²⁸

The international law principle that a state should not use its territory in such a way as to cause damage to another state's territory was subsequently confirmed in a more general context by the International Court of Justice (ICJ),Footnote ²⁹ and has since become one of the key tenets of the new discipline of international environmental law.Footnote ³⁰ It is regarded by respected international jurists as the sole environmental principle that has without doubt crystallized into customary international lawFootnote ³¹ and is ‘sufficiently well-established to provide the basis for an international cause of action’.Footnote ³²

Cases of transboundary environmental damage aside, international environmental law did not exist until well after World War II. A relatively young discipline, it has its origins in the post-World War II efforts of the United Nations Educational, Scientific and Cultural Organization (UNESCO) and, more significantly, in the environmentalist movement of the 1960s and 1970s. It is an oft-forgotten fact that even though, upon its formation, the founding fathers of the United Nations (UN) could not have intended the organization to take on an environmental protection role,Footnote ³³ organs of the UN were already heading in this direction in the 1950s. One of the four specialized agencies under the aegis of the UN's Economic and Social Council, UNESCO had been created in 1945 as a forum of intellectuals and scientists with the aim of increasing international co-operation through the promotion of education, science, and culture in UN member states.Footnote ³⁴ As early as its second session, in 1947, UNESCO launched an International Conference on the Protection of Nature, and in 1948 a conference at Fontainebleau under its guidance saw the creation of the International Union for the Conservation of Nature, the world's first international environmental organization and a key participant in many areas of contemporary environmental law.Footnote ³⁵

However, it was the UN General Assembly, which had become increasingly active in the 1960s as a result of the addition of a number of post-colonial UN member states, that placed environmental protection firmly on the agenda of the international community. It did so in the context of the burgeoning environmental movement of this time, the geographical spread and political intensity of which was most probably the chief cause of the speed with which international society and international law established an environmental branch. In 1962, the New York Times had published extracts of Rachel Carson's famous book on the harmful impact of DDT on birds, Silent Spring, a book that garnered substantial attention for environmental causes, particularly in the US. Then, in 1967, the oil tanker Torrey Canyon ran aground, discharging 120,000 tons of crude oil into the sea near the British coast and awakening the European population in particular to the prospect of large-scale environmental disasters. Against the backdrop of the social upheavals of 1968, in which many protesters also attacked the so-called ‘out of control’ growth of population and consumption, the General Assembly adopted, on the recommendation of UNESCO, a resolution to organize a UN Conference on the Human EnvironmentFootnote ³⁶ which took place in June 1972 in Stockholm – the birthplace of international environmental law.

It should be noted that, despite its rapid evolution since the 1970s, international environmental law has taken a different route in respect of environmental damage to that taken by its domestic law counterpart. Whereas most domestic environmental law systems have gone on to mandate unambiguously that compensation be paid in the event of environmental damage, international environmental law has been far more equivocal as regards the payment of compensation for damage and has instead focused on somewhat vague principles of prevention and precaution. While an obligation to pay reparations would usually be attached to any violation of the well-established sic utere tuo ut alienum non laedas environmental damage rule as a matter of general international law,Footnote ³⁷ it is interesting to note that the main international environmental law expressions of this principle, including Principles 21 and 2 of the Stockholm and Rio declarations respectively,Footnote ³⁸ as well as the International Law Commission's 2001 draft articles on the ‘Prevention of Transboundary Harm from Hazardous Activities’,Footnote ³⁹ do not speak of ex post facto liability, but instead place their emphasis on pre-damage prevention. There are, of course, countless instances of international practice where compensation has in fact been paid for environmental damage,Footnote ⁴⁰ and others have pointed to the growing recognition for the application of the payment aspect of the ‘polluter pays’ principle at an international level.Footnote ⁴¹ However, thorough analyses of state practice have revealed that a state's payment of compensation for its breach of the ‘soft responsibility’Footnote ⁴² obligation not to cause environmental damage is the exception rather than the norm.Footnote ⁴³

It can therefore be concluded that contemporary international environmental law focuses more on prevention before the fact than the distribution of justice after the fact of environmental damage. Prevention is the main strategy adopted by countless prominent international environmental law instruments adopted since the Stockholm Conference, including the wildly successful Vienna Convention/Montreal Protocol regime for the protection of the ozone layerFootnote ⁴⁴ and the universally known, even if somewhat less successful, Framework Convention and Kyoto Protocol in respect of anthropogenic emissions that contribute to global climate change.Footnote ⁴⁵ Such a focus on prevention in the environmental context (as opposed to a financial context, for example) is understandable when, as pointed out by the ICJ in the Gabčíkovo-Nagymaros Case, one notes the ‘limitiations inherent in the very mechanism of reparation of this type of damage’.Footnote ⁴⁶ Indeed, the practical difficulties of ex post facto compensation for environmental harm are compounded at the international level, where international dispute resolution is not as suited to dealing with problems of proof and the calculation of damages as its domestic equivalents.Footnote ⁴⁷

Nevertheless, the fact that the international environmental law system generally stops at prevention and does not go on to prescribe detailed consequences for violation, as its domestic counterparts do, is perhaps indicative of some weakness in this still young and underdeveloped field of law. Relative to other subsystems of international law, international environmental law places considerable reliance on soft law norms and principles rather than hard norms of customary or treaty law, lacks capable institutional backing (the funding problems at the United Nations Environment Programme are well documented), and suffers from problems with enforcement.

It would be all too easy to attribute the fact that, as we will see, the bulk of the rules on wartime environmental damage were not developed in the international environmental law field to such weaknesses in the structure and form of international environmental law. However, this would ignore the fact that the nature of the subject matter of international environmental law itself often prevents it from claiming ownership to certain areas of international law properly falling within its ambit. Indeed, those who appear to forget or even explicitly deny the existence of international environmental law as a separate branch of international law generally do so on the basis that other areas of international law are often capable, perhaps even more capable, of dealing with environmental problems than the norms and principles belonging to international environmental law itself. Malgosia Fitzmaurice, for example, once went so far as to say that international environmental law is merely a subspecies of state responsibility law,Footnote ⁴⁸ thereby implying that the sophisticated preventative machinery international environmental law has developed in respect of a range of international environmental problems can be largely ignored. Others may point to the fact that the environmental chamber of the ICJ has not yet been used or that the majority judgment even in one of the more famous environmental cases that has come before the ICJ, the Gabčíkovo-Nagymaros Case, arguably just paid lip service to international environmental law rules and principles while arriving at its findings on the substantive legal questions through a methodical application not of international environmental law rules or principles but of the dictates of treaty law and state responsibility law.Footnote ⁴⁹ However, all of this does not serve to show that international environmental law, most appropriately defined as the set of rules and principles aimed at the protection of the natural environment,Footnote ⁵⁰ does not exist, but merely that it rarely, if ever, exists in isolation, hermetically sealed off from the application of other branches of international law. After all, as noted in the introductory part of this article, contemporary international problems are often of such complexity that it is almost inconceivable that one of the many other branches of modern-day international law would not apply simultaneously with international environmental law in relation to an international environmental issue, a fact borne out in recent practice before international courts and tribunals where prominent international environmental law cases overlap with everything from the law on the use of forceFootnote ⁵¹ to international trade lawFootnote ⁵² and human rights law.Footnote ⁵³

It is for this reason that serious practitioners of international environmental law must bring to their work knowledge not just of general international law but also of a range of other areas of international law. For environmental damage in the marine environment, law of the sea is likely to be relevant,Footnote ⁵⁴ and where environmental damage is caused by a foreign investor, investment law will almost certainly come into play.Footnote ⁵⁵ If environmental damage occurs in the context of armed conflict, international humanitarian law and potentially also international criminal law will obviously need to be addressed. It is to the latter interaction that we will devote our attention for the remainder of this article.

International humanitarian law

In the present publication, a general introduction to international humanitarian law is unnecessary, but a few remarks as to how environmental damage may come within its scope should be helpful. The first instruments of international humanitarian law were motivated by the principle of humanity and thus, at least from an environmental law point of view, were highly anthropocentric. However, while the focus of early international humanitarian law was on minimizing direct causes of human suffering among participants in armed conflict, the discipline itself was never restricted in such a way. Indeed, international humanitarian law has its foundations in general exhortations of the Martens clause and, originally, in the call of the International Committee of the Red Cross (ICRC)'s founder, Henry Dunant, to ‘press forward in a human and truly civilized spirit the attempt to prevent, or at least to alleviate, the horrors of war’.Footnote ⁵⁶ Moreover, the first code for the conduct of warfare, the famous Lieber Code adopted by Abraham Lincoln for the use of his Union forces in the American Civil War in 1863, is also quite general in its scope, with its section II on the public and private property of the enemy, containing, for example, several provisions that aim to protect the culturally and scientifically important items and all property belonging to churches, hospitals, or other establishments of an exclusively charitable character.Footnote ⁵⁷

Two aspects of the twentieth-century development of international humanitarian law along more general lines are of particular importance for an understanding of the regulation of wartime environmental damage. First, the progressive expansion of the scope of persons protected by the law of war, from soldiers directly engaged in the conflict to civilians indirectly caught up in it, placed new emphasis on how war affects civilian life and thereby laid the groundwork for international humanitarian law's consideration of the impacts of wartime environmental damage. Second, when the ICRC arguably went beyond the bounds of its primary mandate to assist victims and, in an effort to make a greater practical impact, brought within the scope of international humanitarian law efforts to restrict the use of certain types of weapons deemed inhumane and unnecessary,Footnote ⁵⁸ treaties that could easily be adapted to regulate wartime environmental damage were adopted. It should come as no surprise, therefore, that it was within the system of international humanitarian law, the lex specialis applicable to armed conflict, that efforts to curb wartime environmental damage were first taken.

The applicability of international environmental law instruments during armed conflict

One of the reasons proffered for why regulation of wartime environmental damage was and continues to be developed broadly within the subsystem of international humanitarian law is that international environmental law rules, even if they are legally binding, are often considered not to apply in the event of armed conflict. There are, in the present author's view, two approaches that can be taken to this complex question.Footnote ⁶⁸

Strictly applying treaty law to the issue, all international environmental law instruments would potentially apply in times of armed conflict except the very few that specifically exclude their application in times of warFootnote ⁶⁹ or those from which it can be clearly ascertained that applying their provisions in times of armed conflict was not foreseen by the negotiating parties.Footnote ⁷⁰ In light of the strict interpretation of what constitutes a ‘fundamental change of circumstances’ in the Vienna Convention on the Law of Treaties formulation of the rebus sic stantibus rule, excluding the application of general international environmental law instruments and rules, particularly those dealing specifically with armed conflict, seems extremely difficult as a matter purely of treaty law.Footnote ⁷¹ Indeed, it is difficult to maintain that the drafters of provisions like the Stockholm Declaration's Principle 26 on nuclear weapons did not foresee its application in times of war.

The more common approach to this thorny issue is to avoid the issue of applicability and simply subordinate the application of often vague dictates of international environmental law instruments to the application of more specific and more established rules of international law. This seems to have been the method adopted by the ICJ in its Legality of the Threat or Use of Nuclear Weapons Advisory Opinion where it stated that:

The Court then goes on to list the provisions of international environmental and international humanitarian law that specifically subordinate environmental considerations to the considerations of the laws of armed conflict in line with what it calls ‘the general view according to which environmental considerations constitute one of the elements to be taken into account in the implementation of the principles of the law applicable in armed conflict’.Footnote ⁷³

Given these difficulties likely to be encountered in applying international environmental law provisions in such crossover areas, it is understandable that, especially during the formative years of international environmental law, those concerned about wartime environmental damage turned their attention to the law of armed conflict. However, international humanitarian law of that era fell well short of these states' desire to specifically prohibit wartime environmental damage, at least where it was severe and intended. Instruments such as the Lieber Code of 1863,Footnote ⁷⁴ the Hague Conventions of 1899 and 1907Footnote ⁷⁵ and even the Geneva Conventions of 1949,Footnote ⁷⁶ while sometimes containing provisions on ‘wanton destruction’, did not specifically address the issue of wartime environmental damage, so specific treaty provisions were sought.Footnote ⁷⁷

When states convened in Geneva in 1974 for the Diplomatic Conference for the Reaffirmation and Development of International Humanitarian Law, there was already a significant groundswell of support for the introduction of a provision protecting the natural environment in wartime. Interestingly, the draft text put forward at the commencement of the conference by the ICRC did not contain any specific provision dealing with this issue.Footnote ⁷⁸ However, a wide-ranging group of states put forward proposals for a provision of international law protecting the environment.

One of the first such proposals was made, ironically, by Australia on 19 March 1974, a state that had earlier fought alongside the US in the Vietnam War but, by the time of the Geneva conference, was being run by a pioneering new government that had ended Australia's involvement in the Vietnam War and was in the process of passing a raft of highly progressive pieces of legislation.Footnote ⁷⁹ The provision suggested by the Australian delegation not only prohibited the use of wartime methods harming the environment and reprisals against the environment, but also made any violation of these prohibitions a ‘grave breach’,Footnote ⁸⁰ thereby entailing individual criminal liability enforceable through universal jurisdiction. However, opposition from, among others, the United Kingdom, eventually resulted in the Australian provision – and similar proposals put forward by the German Democratic Republic, Czechoslovakia, Uganda, and Vietnam – being substantially watered down.Footnote ⁸¹ As a result, the relevant provisions of Additional Protocol I as it was signed,Footnote ⁸² while prohibiting reprisals against the natural environment (Article 55(2)), introduced a qualifying mental element for the prohibition on the use of methods of armed conflict damaging the environment (Articles 35(3) and 55(1)) and did not make violation of either of these provisions a ‘grave breach’ under the Protocol such as to entail individual war crimes responsibility (see Article 85 of Additional Protocol I). Further, no environmental provisions were included in Additional Protocol II,Footnote ⁸³ which regulates non-international armed conflict, reportedly on the basis that rebel forces fighting in civil wars were unlikely to apply international humanitarian law anyway and their actions would therefore be better addressed through the human rights framework.Footnote ⁸⁴

Between the first and second sessions of the 1974–1977 Geneva Conference that produced Additional Protocol I, the Soviet Union submitted to the UN General Assembly a draft international convention on the prohibition of action to influence the environment and climate for military and other purposes and proposed that an international convention along these lines be adopted.Footnote ⁸⁵ The General Assembly accepted this proposal and, after the United States co-operated with the USSR in its drafting,Footnote ⁸⁶ the Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques (the ENMOD Convention) was already set to be adopted by the General Assembly on 10 December 1976, prior to the conclusion of the Geneva Conference and the adoption of Additional Protocol I.Footnote ⁸⁷ While it has received criticism from environmentalists for its limited scope,Footnote ⁸⁸ the ENMOD Convention remains the first and only instrument specifically focusing on the protection of the environment in armed conflict.Footnote ⁸⁹ It is neither a Convention that prosecutes wartime environmental damage as such nor a Convention that bans the use of certain weapons, but rather an effort to restrict the use of certain techniques in armed conflict such as those that had been employed by the US military in Vietnam.

Neither of these two instruments – nor the weak provisions of subsequent instruments spawned either by the international humanitarian law branch (such as the heavily qualified 1982 CCW Protocol on Prohibitions or Restrictions on the Use of Incendiary Weapons provision)Footnote ⁹⁰ or by the international environmental law branch (such as the vague, soft law articles in the General Assembly's 1982 World Charter for Nature Footnote ⁹¹ and Agenda 21,Footnote ⁹² which simply urge protection of the environment in armed conflict) – proved particularly effective in preventing subsequent wartime environmental damage. As described above, the 1980s and 1990s witnessed some of the most egregious acts against the environment during armed conflict. It is submitted that there are three main reasons for this apparent failure.

As regards the more specific, further-reaching 1970s provisions, first, neither the ENMOD Convention nor Additional Protocol I prohibits environmental damage occurring in non-international armed conflicts such as insurrections by rebels and full-blown civil wars.Footnote ⁹³ Many of the instances of wartime environmental damage in the 1980s and 1990s occurred in the context of non-international armed conflicts, such as the Guatemalan Civil War where Agent Orange-style defoliants were reportedly used in regions of guerrilla activity; in the Salvadoran Civil War, where napalm and white phosphorus are understood to have been used; and in the early part of the Kosovo conflict, where Serb forces are alleged to have poisoned wells and adopted scorched earth tactics against ethnic Albanians.Footnote ⁹⁴

Secondly, the environmental damage provisions of the 1976–1977 instruments are only binding on the states who have signed them, unless they are deemed reflective of customary international law. In light of prior and subsequent state practice, it is difficult to see how these provisions could be considered customary international law applicable against some of the most militarily active states, which had refused to ratify them.Footnote ⁹⁵ There are presently 167 parties to Additional Protocol I, but these do not include the US, Israel, Iraq, and Iran; while the ENMOD Convention has only been ratified or acceded to by 72 states, not including France and most Middle Eastern states. Most major incidents of post-1980 wartime environmental damage were therefore committed by states not party to these international agreements, including the Iraqi use of oil installations in the Iran–Iraq and Persian Gulf wars, the US-led NATO bombings in Kosovo in 1999 (particularly at industrial complexes in Pančevo and around Novi Sad), and the Israeli actions in Lebanon and Gaza. More will be said about these incidents below, but it suffices to note for present purposes that neither Iraq nor Israel (which were and are still not party to either agreement), nor the US (whose environmental damage was not attributable to the use of environmental modification techniques and which was not a party to Additional Protocol I) was subject to an international law treaty regime that could have rendered them in breach of an international obligation not to damage the environment in armed conflict.

Thirdly, as noted in the above history as to how these provisions were adopted, the environmental protection norms as set out in both these instruments – like most norms in the Geneva Conventions and Additional Protocols – are not considered ‘grave breaches’ under international humanitarian law; violations of them therefore only entail a weak obligation on states to repress such breaches and potentially state responsibility with, at most, consequences such as reparations and possibly international co-operation against the offending state.Footnote ⁹⁶ Indeed, the civil liability aspect of international humanitarian law is underscored by Article 91 of Additional Protocol I, which makes a ‘Party to the conflict which violates the provisions … if the case demands … liable to pay compensation’.Footnote ⁹⁷ The practical limitations of enforcing a system of state responsibility on states already involved in armed conflict are obvious. Indeed, the basis for the enforcement of the decentralized and consensual international legal system rests on the often vain hope that states will apply international law and settle their disputes in good faith, but armed conflict generally indicates a reluctance to apply international law rules and to co-operate in such a manner as to settle disputes peacefully.Footnote ⁹⁸ In addition, international law's last-resort, United Nations system of sanctions is, as Sassòli notes, in such politically charged contexts often governed by ‘arbitrary and selective political decisions of States’ and undermined by the use of the veto at the UN Security Council empowered to decree sanctions.Footnote ⁹⁹ Such problems caused Birnie and Boyle, writing from an international environmental law perspective, to comment that ‘the law of armed conflict is one of the least sophisticated parts of contemporary international law’, with no means to ‘afford adequate assurance of military restraint’.Footnote ¹⁰⁰

The criminalization of international humanitarian law norms as an effort to ensure greater compliance

International humanitarian law's response to these issues, particularly the third problem, was to criminalize certain particularly serious violations of the Geneva and Hague Conventions and their protocols in the hope that, by raising the spectre of personal criminal liability for politicians or military commanders, they would at least be discouraged from carrying out the most serious and inexcusable acts.

However, the ‘grave breaches’ regime of the Geneva Conventions and Additional Protocols is itself subject to important practical limitations. For all grave breaches, international humanitarian law creates universal jurisdiction and requires states to enact legislation either for prosecuting and trying persons alleged to have committed, or to have ordered to be committed, such crimes, or for extraditing those persons to another High Contracting Party for trial.Footnote ¹⁰¹ Yet few states have introduced such legislation or taken such action in their national courts, and, where there is legislation and enforcement, how the rules are applied has often greatly diverged across systems.Footnote ¹⁰² In branding the Geneva law's provisions on national jurisdiction over grave breaches ‘a dead letter’, Cassese cites as possible reasons for this failure, first, the reluctance of states to prosecute, or expose to prosecution, their own nationals, and second, political and diplomatic considerations frequently causing states to refrain from prosecuting foreigners.Footnote ¹⁰³ Indeed, many of the few cases conducted in national courts relate to the events of World War II,Footnote ¹⁰⁴ the most famous of which only came to pass after the lawless Israeli abduction of Adolf Eichmann in violation of Argentina's territorial sovereignty. The vast majority of other prosecutions for grave breaches have only been possible in tribunals specially constituted by the winners of the relevant war, including in the ad hoc international criminal tribunals established by the Security Council taking a broad view of its powers under Chapter VII of the UN Charter. As Sharp has provocatively argued, an international legal order that is dependent on such actions as one sovereign invading or interfering with the territorial sovereignty of another is a dubious foundation for a stable rule of law.Footnote ¹⁰⁵

As the result of such reliance on external factors, the international humanitarian law regime revealed itself to be in need of bolstering if it were to achieve the outcome of comprehensive punishment and powerful deterrence for which the grave breaches regime had been established. Unfortunately, little could be done about this in the fragmented international community of the cold-war era, but the fall of the iron curtain ushered in a decade of internationalist optimism in which the concept of an international criminal court enjoying wide jurisdiction to try individuals for such violations was revived.Footnote ¹⁰⁶

The International Criminal Court (ICC) came into being as a result of the entry into force of the Rome Statute of the International Criminal Court (‘ICC Statute’) on 1 July 2002. The Statute differs from statutes promulgated for the earlier ad hoc criminal tribunals by setting out more than simply the main categories of offences over which the Court has jurisdiction and instead providing considerable detail as to the precise crimes for which the Court may find an individual personally criminally liable.Footnote ¹⁰⁷

In respect of war crimes, the ICC Statute spells out, in Article 8(2)(b), twenty-six separate violations over which, if they occur in international armed conflict, the Court has jurisdiction. The war crimes detailed move beyond the grave breaches of the Geneva Conventions (over which jurisdiction is separately established by Article 8(1) of the ICC Statute) and also mark a significant progression from the jurisdiction granted to the ad hoc international criminal tribunals for Rwanda (ICTR) and the Former Yugoslavia (ICTY) by statutes drafted only four of five years earlier. Article 3 of the Statute for the International Criminal Tribunal for the Former Yugoslavia (1993), for example, explicitly mentions only six war crimes over and above the grave breaches of the Geneva Convention – twenty fewer than the ICC Statute.Footnote ¹⁰⁸ For present purposes, it is important to note that that ICTY list contains the ‘employment of poisonous weapons or other weapons calculated to cause unnecessary suffering’ (Article 3(a) of ICTY Statute) and the ‘wanton destruction of cities, towns or villages, or devastation not justified by military necessity’ (Article 3(b)), but does not include any explicit criminalization of general wartime environmental damage. Even though this list is explicitly stated not to be exhaustive, under the test laid down by the ICTY Appeals Chamber presiding in the Tadić Case, it is extremely unlikely that the rule in Articles 35(3) and 55(1) of Additional Protocol I, not listed as a grave breach by the aforesaid instrument, could meet the requirement that a violation of its terms attracts individual criminal responsibility as a matter of customary international law.Footnote ¹⁰⁹

Clearly then, by explicitly attaching individual criminal liability to certain instances of wartime environmental damage in its Article 8(2)(b)(iv), the ICC Statute has moved further than the non-grave-breach provisions of Additional Protocol I and also the statutes of the ad hoc international criminal tribunals for Rwanda and Yugoslavia. Significantly, the ICC Statute does not end its list of war crimes at the acts considered grave breaches, and therefore attracting individual criminal responsibility under the Geneva Conventions and Additional Protocol I. It is indeed a tribute to the somewhat unexpected success of the Rome Conference that it was able not merely to achieve a crystallization of existing customary international law, but also to contribute to the progressive development of that law in certain key respects, including the criminalization of what Richard Falk had famously termed ‘ecocide’.Footnote ¹¹⁰

Without doubt, the addition of a provision attaching criminal liability to instances of wartime environmental damage significantly bolsters the international legal regime governing this type of act. Within the humanitarian law structure, the imposition of criminal liability is regarded as the furthest that legal regulation can reach and the sanction most likely to produce greater long-term compliance with the laws of war.Footnote ¹¹¹ Indeed, as noted by the Nuremburg tribunal in 1947:

Interestingly, criminal liability is viewed in a very similar manner in environmental law. While international environmental law has not yet reached the stage of evolution where it can think in general terms about imposing criminal liability for breaches of its norms, many domestic environmental law systems use criminal responsibility as a key part of their regulatory armoury. In adopting a directive on the protection of the environment through criminal law in 2008, the European Parliament noted the importance of criminal penalties, saying in its third preambular paragraph:

Domestic environmental law systems are replete with examples of where criminal penalties have been introduced to increase compliance with laws protecting against environmental damage. The US Clean Air Act, for example, prescribes criminal penalties involving fines and/or imprisonment of up to five years in length for flagrant failures to comply with environmental law obligations,Footnote ¹¹⁴ and fines and/or imprisonment of up to fifteen years for the most egregious acts of air pollution.Footnote ¹¹⁵ In Spain, the possibility of penal sanctions for environmental breaches is even set out in the country's constitution,Footnote ¹¹⁶ while in South Africa ‘[c]riminal enforcement power is the most widely prescribed for implementation of environmental law’.Footnote ¹¹⁷

By imposing a state responsibility obligation that ultimately entails the payment of damages for less serious acts of wartime environmental damage (the equivalent to a civil law obligation in domestic law), then individual criminal liability for more serious acts, the existing international legal regime in respect of wartime environmental damage can be seen, on a very general level at least, to be in keeping with the general approaches and internal logics of domestic and international forms of both humanitarian and environmental law.

This does not mean, of course, that the precise legal consequences associated with each type of wartime environmental damage in each type of situation are sure to be appropriate, be they viewed from the international humanitarian/international criminal law or the (international) environmental law perspective. Indeed, such an evaluation can only be made once the specifics of the norms regulating wartime environmental damage, including the ICC Statute provision, which attaches criminal liability to its commission (Article 8(2)(b)(iv)), have been analysed in greater detail.Footnote ¹¹⁸

The range of acts prohibited by each of the relevant rules

The first norm to be adopted in respect of wartime environmental damage, the ENMOD Convention, appears to be narrower than the later provisions in terms of the range of acts that fall within the prohibition. While its Article II definition of what constitutes an environmental modification technique is quite broad, the set of illustrative examples in the Understandings appended to the Convention (CCD Understandings) by the Geneva Conference of the Committee on Disarmament and adopted by the UN General Assembly appears to place undue restriction on the scope of this rule.Footnote ¹²¹ Indeed, as pointed out by Jozef Goldblat shortly after the Convention was adopted, it appears that the Convention is a half-measure clearly prohibiting only fanciful events such as the triggering of earthquakes, while environmental modification techniques more likely to be adopted during armed conflict, such as certain instances of river diversion or strategic cloud seeding, do not seem to be prohibited.Footnote ¹²²

Additional Protocol I and the ICC Statute are, however, much more general in terms of the range of acts that may, under certain circumstances, lead to responsibility for wartime environmental damage. Articles 35(3) and 55(1) of Additional Protocol I speak in general terms of ‘methods or means’ that cause damage to the environment, while Article 8(2)(b)(iv) of the ICC Statute speaks of an ‘attack’. The Elements of Crimes document adopted by the Preparatory Commission for the International Criminal Court (PrepCom) shortly after the signature of the Statute makes it clear that attack should be interpreted in the general sense of ‘acts of violence against the adversary, whether in offence or in defence’ (as defined in Article 49(1) of Additional Protocol I) and not confused with the special, jus ad bellum, sense of how this term and its cognates, including ‘armed attack’, are used in the UN Charter.Footnote ¹²³

The use of notions such as ‘hostile use of technique’ (ENMOD), ‘methods or means’ (Additional Protocol I), or an ‘attack’ (ICC Statute) in defining the scope of acts prohibited, is the first clear sign that the provisions that constitute the current international legal regime against wartime environmental damage were clearly adopted in accordance with the logic of international humanitarian law and not according to the principles and approach of international environmental law. The scope of the ENMOD Convention in particular may be somewhat disturbing to someone viewing these norms from an environmental law perspective, not only because it unduly restricts the range of techniques but also because it targets only those situations where the environment itself was effectively used as a weapon, thereby excluding all other situations of incidental damage to the environment in international armed conflict. Even the more general norms of Additional Protocol I and the ICC Statute are liable to a certain degree of such criticism from this perspective, as there may be situations where the environment is greatly damaged in wartime as part of events that neither constitute environmental ‘methods or means of warfare’ (Additional Protocol I) nor offensive or defensive acts of violence against an adversary (ICC).

An applicable test for causation?

In terms of causation, none of the relevant provisions specifies what exactly this might require in the circumstances. ENMOD speaks of ‘having [certain] effects’, Additional Protocol I of methods that ‘are intended, or may be expected, to cause’ certain damage, and the ICC Statute provision simply uses the expression ‘will cause’ the damage.Footnote ¹²⁴

Without any authoritative explanations or jurisprudence showing what test for causation is likely to be used, it is impossible to evaluate whether the international legal regime for wartime environmental damage approaches questions of causation more in the style of international humanitarian law or of international environmental law. Suffice to say that, if the opportunity to develop such a test eventually arises in relation to environmental damage, the court, tribunal, or other institution may well begin by placing itself within the frame of how causation has been understood in relation to other breaches of international humanitarian law. Yet an international environmental lawyer would prefer to tailor the rules of causation to the specific situation of environmental damage and would prefer such a body not to rely on general humanitarian law notions, but instead on the theory of causation elaborated precisely in relation to environmental damage.

The United Nations Compensation Commission (UNCC) established to compensate victims of the Gulf War for harm they suffered, including environmental harm, is one such source of jurisprudence for the causation of environmental damage to which international environmental lawyers would refer the ICC. This commission had been established by a UN Security Council resolution that held Iraq ‘liable under international law for any direct loss, damage, including environmental damage and the depletion of natural resources, or injury to foreign Governments, nationals and corporations, as a result of Iraq's unlawful invasion and occupation of Kuwait’.Footnote ¹²⁵ The UNCC Panel of Commissioners for ‘F4’ claims (environmental damage claims) drew on tests for causation elaborated in the context of peacetime environmental damage to determine what constituted a direct cause, taking a very liberal approach to ‘direct causation’ in one particular case where the Commissioners held that, even where there were intervening events, a direct causal link could be established so long as those events did not break the chain of causation.Footnote ¹²⁶

It should be noted that this UNCC test for the ‘direct causation’ of environmental damage is much more lenient than equivalent tests used in relation to non-environmental international humanitarian law norms. For example, the ICRC's recently published Interpretive Guidance on the Notion of Direct Participation in Hostilities Under International Humanitarian Law, says that: ‘direct causation should be understood as meaning that the harm in question must be brought about in one causal step [such that] … conduct that … only indirectly causes harm, is excluded from the concept of direct participation in hostilities’.Footnote ¹²⁷

Widespread, long-term, and/or severe damage to the natural environment

The type and extent of environmental damage that must be caused to trigger the application of the rules prohibiting wartime environmental damage is probably their most important element. The formulation ‘widespread, long-term and severe damage to the natural environment’ (emphasis added) is used in all of Additional Protocol I's Articles 35(3) and 55(1) and Article 8(2)(b)(iv) of the ICC Statute. Hence, in terms of the environmental damage caused, the ICC Statute's criminalized form of the prohibition, unlike certain prior draft criminal environmental damage provisions,Footnote ¹²⁸ does not differ from Additional Protocol I's humanitarian obligation except as regards the ICC Statute's additional requirement that the damage be ‘clearly excessive in relation to the … military advantage anticipated’ – the element of the ICC Statute provision that will be discussed in the final sub-section of the present analysis.

Before turning to the ‘widespread, long-term and severe damage’ formula, it should be noted that what constitutes the ‘natural environment’ is neither defined in these instruments nor the object of consensus. Indeed, as Jensen goes to substantial lengths to demonstrate, there is not yet a generally accepted definition of the ‘environment’ let alone the ‘natural environment’ and even the widely referenced scientific and comprehensive definition of Article II of the ENMOD Convention, in Jensen's view, provides little clarity.Footnote ¹²⁹ Alexandre Kiss argues that the adjective ‘natural’ seems to exclude urbanized or industrial zones,Footnote ¹³⁰ while the ILC's 1991 Commentary to its Draft Code of Crimes Against the Peace and Security of Mankind contains a broader interpretation of ‘natural environment’.Footnote ¹³¹ In light of ever-increasing consciousness of the fragility of the environment, one might suggest abandoning the Kiss interpretation in favour of a more contemporary, broader view that more closely resembles the ENMOD definition.

In terms of the scope of application of Articles 33(5) and 55(1) of Additional Protocol I and Article 8(2)(b)(iv) of the ICC Statute, it is of vital importance to note that the provisions use the conjunctive element ‘and’ to link the three adjectives qualifying the damage to the natural environment. This means that ‘widespread damage’, ‘long-term damage’, and ‘severe damage’ are cumulative conditions, all of which must separately be met in order for there to be a breach of the relevant provision. Greater environmental damage is accordingly required than that which would potentially constitute a breach of Article I of the ENMOD Convention, an instrument that uses the less demanding, disjunctive formula of ‘widespread, long-lasting or severe’.Footnote ¹³²

The precise meanings of the separate elements ‘widespread’, ‘long-term’, and ‘severe’ were the subject of long discussions at the Geneva Conference for Additional Protocol I,Footnote ¹³³ but remain shrouded in ambiguity.Footnote ¹³⁴ Commenting on a draft provision drawn from Article 55(1) of Additional Protocol I in 1991, the ILC simply described these elements as cumulative factors to determine the seriousness of a crime, with little guidance as to the thresholds to be applied.Footnote ¹³⁵ The ICC Elements of Crimes document of 1998 does not specify the meaning of these terms so, in a search for clarity, one must return to the older official and unofficial commentaries regarding the meaning of these same terms as they were used in the ENMOD Convention and Additional Protocol I.

The mental elements of the crime

The well-established criminal principle of actus non facit reum, nisi mens sit rea means that while the ENMOD Convention and Additional Protocol I may attach state responsibility to acts causing widespread, long-term, and severe damage to the environment, individual criminal responsibility will only ensue where such acts are intentional and undertaken in the knowledge that they would cause such damage. Given the above-noted weaknesses of enforcing state responsibility regimes such as ENMOD and Additional Protocol I and the great potential of the ICC Statute provision for ensuring greater compliance with rules prohibiting wartime environmental damage, it is important to evaluate in detail the limitations that these mental elements may place on enforcing legal consequences for damage to the environment in international armed conflict.

Article 8(2)(b)(iv) of the ICC Statute speaks of ‘[i]ntentionally launching an attack in the knowledge that such attack will cause … widespread, long-term and severe damage to the natural environment …’. Unlike some war crimes that do not specify the nature of the mental element,Footnote ¹⁵¹ this provision avoids the difficulties posed by the much-contested ‘intent and knowledge’ drafting of ICC Statute's general, default provision on the mental elements of crimes (Article 30). As pointed out by Werle and Jessberger, intent and knowledge have different meanings depending on the elements to which they are connected.Footnote ¹⁵² By specifying intent as an adverbial qualifier exclusively of the launching of the attack and knowledge as solely relating to the consequences of the act, Article 8(2)(b)(iv) of the ICC Statute associates intent only with the relevant conduct and associates knowledge solely with the relevant consequences. This in turn reveals two distinct mental elements: (1) an intent to launch an attack; and (2) the knowledge that such an attack will cause environmental damage. We will now deal with each of these required mental elements in turn.

The proportionality ‘defence’

The environmental damage provision of the ICC Statute does not simply require an act causing widespread, long-term, and severe damage to the natural environment, an intention to commit that act, and knowledge that it would cause that damage, but also demands that such damage is ‘clearly excessive in relation to the concrete and direct overall military advantage anticipated’.Footnote ¹⁷²

On the one hand, it seems justifiable that a further requirement be introduced to distinguish the more serious criminal offence from the violation of humanitarian law. However, compared to the parallel Additional Protocol I provisions, the ICC Statute already contains a stricter causality and a more demanding knowledge requirement (see sub-sections above). Providing, in addition, a very open proportionality requirement that, through its link to an ‘overall military advantage anticipated’, effectively amounts to a wide defence of necessity seems to give perpetrators yet another way to avoid the application of a provision that, in light of the analysis undertaken in the previous five sub-sections, it already appears extremely difficult to apply to many instances of intentional wartime environmental damage.

This proportionality requirement-cum-defence, like other elements of Article 8(2)(b)(iv) of the ICC Statute seems to have its origins in provisions relating to its other limb, civilian damage, including Additional Protocol I's Article 51. Indeed, the proportionality requirement in relation to civilians dates from a UK claim in relation to the 1938 Spanish Civil War.Footnote ¹⁷³ A consequence of the ICC Statute's combination of civilian damage and environmental damage into the one provision therefore appears to be that proportionality with a military advantage has, for what appears to be the first time in any international instrument relating to wartime environmental damage, become a defence for any perpetrator of such damage. This defence is one of the most enduring elements of classical international humanitarian law, having featured prominently in the aforementioned Lieber Code, which was so expansive in its definition of the defence that it was sometimes construed as a licence to contravene the laws of war.Footnote ¹⁷⁴ Yet, as Carnahan notes, the Lieber Code's necessity defence is increasingly seen as out of sync with contemporary international humanitarian law norms that protect the civilian population and the environment, and is ‘widely regarded today as an insidious doctrine invoked to justify almost any outrage’.Footnote ¹⁷⁵

In this context, one can understand the ‘astonishment’ expressed by Allain and Jones in response to the inclusion of what is in effect a defence of military necessity, which they argue ‘runs counter to … the whole spirit of the times, which recognises that the infliction of such damage on the natural world cannot be tolerated in any circumstances’.Footnote ¹⁷⁶ The ICRC authors of a study on the elements of ICC crimes, on the other hand, claim that this result was not only intended but indeed reflects the opinio juris of the international community as regards wartime environmental damage.Footnote ¹⁷⁷ This view is supported by authoritative pieces of evidence including the ICJ's Nuclear Weapons Advisory Opinion, which, as Freedland points out, declined to promote the protection of the environment above questions of military necessity,Footnote ¹⁷⁸ by urging that environmental considerations be taken into account ‘when assessing what is necessary and proportionate in the pursuit of legitimate military objectives’.Footnote ¹⁷⁹ A General Assembly Resolution on the ‘Protection of the environment in times of armed conflict’ provides further support to this claim as it also makes this link, speaking of environmental destruction that is ‘not justified by military necessity and carried out wantonly’.Footnote ¹⁸⁰

In terms of the precise meaning of the Article 8(2)(b)(iv) of the ICC Statute proportionality requirement, it should be noted that it goes further than Article 51(5)(b) of Additional Protocol I (and other instruments using identical wording)Footnote ¹⁸¹ by adding the word ‘overall’ to the ‘concrete and direct military advantage anticipated’ and the word ‘clearly’ to the requirement that the damage be ‘excessive’. There are no other international legal sources using the precise phraseology of the ICC Statute, so these slightly different terms were not simply borrowed but rather reflect a specific effort at the Rome Conference to expand the defence of proportionality with a military objective. Indeed, whereas some delegations at the Geneva Conference (such as Australia, New Zealand, Germany, and Canada) considered the addition of the word ‘overall’ a mere improvement on the drafting of the Additional Protocol I provision, several delegations worried that it would allow the long-term advantages of winning the war per se to be taken into account. Solf's use of the word ‘overall’ in his analysis of Article 52 of Additional Protocol I implies consideration of the entire military operation as a whole rather than the specific military objective.Footnote ¹⁸² Following his logic, the word overall would enable the application of the defence of proportionality to a situation such as the Allied bombing campaign in the Pas de Calais, which was unnecessary in the specific sense, but necessary as part of the overall purpose of distracting German forces from the Allies' subsequent landings on the beaches of Normandy.Footnote ¹⁸³

The more significant way in which Article 8(2)(b)(iv) of the ICC Statute expands the proportionality defence is through the addition of the word ‘clearly’ before ‘excessive’.Footnote ¹⁸⁴ After all, almost any defendant coming before the Court, having intrinsically launched an attack in an international armed conflict, is likely to plead the defence of proportionality with his or her army's military objectives. One might suggest that it would be a brave court indeed who would go so far as to say that actions were ‘clearly excessive’ (‘manifestement excessifs’ in the French version) to the military advantage described.

In this regard, Weinstein directs our attention to what she calls ‘the only case in history where military necessity was balanced against environmental damage’:Footnote ¹⁸⁵ the Nuremberg Tribunal's prosecution of the Austrian general Lothar Rendulic in US v. Wilhelm List & Ors (1948).Footnote ¹⁸⁶ Rendulic was not found guilty in relation to scorched earth offences in Norway on the basis of military necessity, even though the necessity did not exist in fact but only in Rendulic's mind – he had proceeded from the false assumption that the Russians were advancing. Far from providing a narrower interpretation of a defence that, it must be recalled, did not use the wider phrase ‘clearly excessive’, this decision merely serves to show just how broad even the unexpanded defence is, so much so that it probably even extends to subjectively determined necessity rather than objective necessity.

A brief consideration of the two main instances of wartime environmental analysis that sparked the international community's desire to prohibit attacks against the environment – US actions in Vietnam and Iraq's actions in Kuwait – further demonstrates the considerable breadth of this defence. If a US general who had directed the spraying of defoliants over vast tracts of Vietnamese territory were tried under such a provision, he would be likely to point to the US military's need to remove the jungle cover exploited against it by Vietcong fighters. Would a court be able to determine that the damage caused to the foliage, most of which subsequently grew back, was clearly excessive to the military advantage obtained by pursuing this objective? It would seem equally difficult in relation to the Iraqi forces who supposedly ignited oil wells to create a smoke cover against US aircraft and jettisoned millions of barrels of oil into the Persian Gulf to obstruct US naval movements. Given that the environmental consequences of these actions were not, for a variety of reasons, as catastrophic as they perhaps could have been, could a court determine them to have been clearly excessive in relation to Iraq's aforementioned military objectives? Indeed, it would seem enormously difficult to imagine a situation in which a court would definitely deem the environmental damage caused clearly excessive to the overall military advantage anticipated.

The likely willingness of any future defendants to invoke this defence and insist upon the importance of the military objective being balanced against the environmental damage caused is reflected in the public relations statements made even by those potentially not even subject to the Court's jurisdiction in relation to well-known instances of wartime environmental damage. On 14 July 1999, the New York Times quoted a NATO spokesperson as saying in relation to the incident at Pančevo:

Importantly for the purposes of the present article, the proportionality-cum-necessity defence in Article 8(2)(b)(iv) of the ICC Statute brings into focus the different perspectives taken on the problem of wartime environmental damage by the different branches of public international law. By demanding that the environmental damage caused be balanced against the overall military advantage obtained, this provision provides a classic example of how horizontal conflict between separate subsystems of international law and international relations can occur. Two different value structures are, in effect, being played off against each other: the objective of preventing environmental damage on the one hand, and, on the other, the humanitarian law philosophy of accepting all aspects of armed conflict necessary for the conduct of hostilities.

Balancing international environmental law and international humanitarian law values

Problems also arise when one considers who undertakes this balancing act, where, and in what context. In an ideal world, the environmental damage would be assessed within the bounds of and according to the principles of international environmental law, while the overall military advantage would be apprehended in the international military law or humanitarian law fields used to dealing with such questions. Yet the balancing act must be undertaken by one court or tribunal and one group of decision-makers likely to have the same areas of expertise. With little doubt, a peace-loving environmentalist would place greater weight on the environmental damage and lesser importance on the overall military advantage than a military lawyer or even an international humanitarian lawyer, who might see destruction of the natural environment to fulfil a military objective as more necessary than reasonably available military alternatives that might involve, for example, grave restriction of the rights of enemy non-combatants. Of course, in the case of wartime environmental damage, it would be the ICC that would have to mediate between the values of different fields of international relations and the distinct approaches of different areas of public international law. Could this pose problems from the perspective of international environmental law?

International environmental law is, for the various reasons stated above, quite accustomed to decision-makers from ‘foreign’ subsystems of international law measuring the importance of an environmental objective against the philosophy of another branch of international law. Indeed, much of the trade and environment debate that briefly became so characteristic of inter-subsystem interaction grew out of the extraordinary interest shown within environmental circles for the WTO's Shrimp-Turtle case.Footnote ¹⁸⁸ In that case, the first panel had in general terms found that an extra-territorial environmental measure undermined the structure of the multilateral trading system and could therefore not come within the general exceptions of Article XX of the General Agreement on Tariffs and Trade (GATT). This jurisprudence was overturned on appeal to the Appellate Body, who set out a more balanced approach, less heavily biased in favour of trade values. However, the fact remains that non-trade values, including environmental values, continued to be weighed against trade values in WTO adjudicatory bodies, panels, and an Appellate Body composed most commonly of experts in trade law supported by secretariat staff again more comfortable with the highly specialized area of international trade law than with general international law or the details of other, particularly non-economic, subsystems of international law.

Parts of the tests in the general exceptions in GATT, Article XX are analogous to the necessity defence for wartime environmental damage. Indeed, according to the WTO jurisprudence under GATT, Article XX(b), the importance of the public policy goal sought by a government measure will be weighed and balanced against various factors, including, most significantly, the trade restrictiveness of the measure.Footnote ¹⁸⁹ Recently, the WTO Appellate Body has focussed on the necessity of the measure and in doing so has asked the parties taking the measure to protect the environment to prove that there was not a less trade-restrictive alternative available.Footnote ¹⁹⁰ As general international law on proportionality and necessity reveals,Footnote ¹⁹¹ such a less restrictive alternative approach is a logically appealing way of dealing with an evaluation of necessity or ‘excessiveness’ and could easily be used by the ICC considering a plea that wartime environmental damage was not clearly excessive to the overall military advantage obtained. If the WTO law or general law approach to necessity were followed at the ICC, the prosecutor's pleadings would then have to suggest ways in which the overall military advantage could have been obtained with a lesser impact on the environment. While this seems to open up a new route toward eventual conviction, the evidentiary complications are patent, further restricting the likelihood of criminal sanctions for a military officer who engaged in wartime environmental damage.

Of course, there is always the chance that the judges on the International Criminal Court will respond well to the delicate balancing-of-interests tasks vested in them by this ICC rule on environmental damage. Indeed, some environmental law commentators have praised the environmental contribution of the WTO Appellate Body, at least in a notable period in which it had some prominent general international lawyers with wide-ranging experience in different fields of public international law sitting on its bench.Footnote ¹⁹² Yet, the danger remains that as part-environmental-law cases move into courts and tribunals with their own ideologies and special areas of expertise, the distinct international environmental law philosophy will eventually be drowned out, never to resurface.Footnote ¹⁹³

Ultimately, from an international environmental law perspective one must ask the question of whether it is better to have environmental rules enforced by another subsystem's court or tribunal on the basis largely of that other subsystem's philosophy or, alternatively, for them not to be enforced at all. In the absence of any proprietary international environmental law court, tribunal, or enforcement structure, should this field of international law really react negatively to the fact that other subsystems are taking a keen interest in environmental protection and bringing their greater institutional force to bear in order to achieve greater compliance with international law principles? After all, we have already seen how international humanitarian law has effectively reached out to the more closely related, but at the same time distinct, field of international criminal law in the hope that a different set of remedies may improve compliance with its rules. Along the way, sacrifices have been made. In order to fit in with the criminal law philosophy, which comes with penalties including incarceration, the combined system requires mental elements such as intention and knowledge before conviction. Of course, the fit between international humanitarian law and international criminal law is much better than those involving international environmental law and these branches, international humanitarian and international criminal law ultimately dealing with the same subject matter according to a predominantly shared set of values. However, it cannot be denied that, even in relation to problems overlapping with areas of international law with which it does not have any particular affinity, international environmental law may, in certain cases, be very well served by employing another subsystem's framework, particularly for the purposes of enforcement of its norms.

Perhaps on the basis of a recognition of this point, the majority of the criticism of what are essentially international humanitarian law and international criminal law instruments regulating wartime environmental damage is focused not on the fact that the rules do not sit within a properly environmental structure and may potentially corrupt it, but on the fact that, from an environmental perspective, these rules do not go far enough.

Too weak a regime from the perspective of international environmental law?

In the contemporary world of international humanitarian law, individual criminal penalties, be they applied through state courts, ad hoc tribunals, or the ICC, are often seen as the best available method for safeguarding compliance with international humanitarian law norms. At first blush, therefore, environmental campaigners should be delighted to see rules on wartime environmental damage that were previously not even part of the grave breaches regime elevated to the status of war crimes at the International Criminal Court. However, as the above analysis of the elements of Article 8(2)(b)(iv) of the ICC Statute and how they would apply to classic examples of intentional wartime environmental damage has shown, the scope of this rule's application is extremely limited. Indeed, with the high threshold requirements for the damage caused, the complex knowledge requirement, and the specially enhanced and thus overly available proportionality/necessity defence, one may wonder, with Heller and Lawrence, whether it is even possible to convict someone under this ICC provision for wartime environmental damageFootnote ¹⁹⁴ – all the more when one considers that we must strictly construe any definition of a crime without extending it by analogy and, in the case of ambiguity, by leaning towards the interpretation favourable to the person being prosecuted.Footnote ¹⁹⁵ Arguably, any military act capable of falling within the ambit of Article 8(2)(b)(iv) of the ICC Statute would be so severe and inexcusable that it would probably fall within the ambit of other international crimes anyway.

ICC Statute, Article 8(2)(b)(iv) may have appeared to commentators at first sight to be a ground-breaking gain for protection of the environment in armed conflict, but seems on closer inspection to be but a mirage, unlikely ever to play a role in addressing the problem of intentional wartime environmental damage through international criminal prosecution. Indeed, a contributor to this Review arrived at a very similar conclusion ten years ago,Footnote ¹⁹⁶ even before the United States had effectively taken such a large chunk out of the ICC's jurisdiction by signing so-called ‘Article 98 agreements’ with more than 100 different states.

Yet steps in any new and worthy direction, even if they are only very small, should nonetheless be lauded. After all, supporters of environmental causes and international environmental lawyers should themselves be all too aware of the difficulties involved in progressing rapidly toward hard, far-reaching international law on a new topic. Arguably, if the international environmental law movement had already reached a higher stage of development and formed a stronger institutional structure, a farther-reaching norm might have been adopted at the Rome Conference. It is all too easy for diplomats to hold the mirror up to the weaknesses of another field and areas of that field that have not been regulated as an excuse for inaction or only the smallest of steps. Such temptation was resisted in relation to wartime environmental damage, the criminalization of which must therefore, in the present author's view, be seen as the passing of a new frontier for international environmental law. No other area of this discipline even comes close to such severe consequences as incarceration for the breach of the terms of an environmental treaty or for international acts that damage the natural environment. Treaties such as the Basel Convention declare certain acts illegal but provide no enforcement measures, merely making a vague call to state parties to use domestic measures to enforce Convention rules.Footnote ¹⁹⁷ Even the Additional Protocol I provisions on wartime environmental damage should be lauded because they sit in a relatively small group of international environmental law rules by which a state can be held responsible for damage it caused even if such damage was not specifically intended, subjectively foreseeable, or reckless.

Viewed in the context of the present state of international environmental law, therefore, the criminalization of wartime environmental damage, far from not going far enough, may actually seem to have gone too far. Is it really right, from a legal policy point of view that the crew of a ship that disgorges toxic waste into the high seas, or the director of a company that takes the decision to pollute an international watercourse, should not necessarily be sent to prison, while a military commander, whose raison d'être is to inflict harm on his enemies, may end up spending time in prison on the basis of the incidental environmental harm that his military activities caused?

In a field such as international environmental law, where the guiding objective is greater protection of the environment by painting new international legal rules on a still relatively empty canvas, any new environmental norms will be welcomed irrespective of any apparent imbalances they may seem to create or contradictions of notions of basic fairness they may seem to engender. Indeed, it is the nature of international law that some branches of the domain are better regulated and better enforced than others, so international environmental law – many aspects of which depend on different branches – will inevitably be somewhat uneven in terms of how it seeks to protect the environment at the international level. The inevitably haphazard pattern of international law-making ensures that international law cannot follow the legal policy paradigm typical of domestic legal systems, pursuant to which the weight of legal sanction rises in tandem with the seriousness or public policy importance of the breach or offence. Such inconsistency is unavoidably more prevalent in branches of international law devoid of a strong internal structure and also in those domains whose norms are more likely to overlap with those of other areas of international law.

Ultimately, whether an international environmental lawyer considers that the criminalization of wartime environmental damage goes too far or not far enough will depend on his or her preparedness to accept, in the interests of the advancement of law-making in this still young subsystem of international law, both a new, yet limited and imperfect international environmental rule and also a patent lack of evenness regarding what activities within the discipline's scope are in fact regulated.

However, it is submitted that such inequities in what activities are regulated and not regulated will be less acceptable to those accustomed to branches of international law that do not typically rely on somewhat sporadic and often fragmented treaty-making efforts, nor on the institutional support of a wide range of other branches of international law. International humanitarian law is one such system and it is therefore important to consider whether, from this field's perspective, the criminalization of wartime environmental damage creates a similar degree of unevenness as it appears to in the context of international environmental regulation.

Too strong a regime from the perspective of international humanitarian/international criminal law?

Employing the same method as we used for our evaluation of the legal regime for environmental damage in armed conflict from an international environmental law perspective, we should now consider it in relation to other violations of international humanitarian law on a separate international humanitarian law/international criminal law scale. In somewhat less scientific terms, the key question is whether it is even appropriate that an individual military commander can potentially be held personally liable for damage to the environment or whether individual criminal liability should instead be restricted to egregious acts carried out directly against human beings, such as genocide and torture. In this light, one might argue that by criminalizing wartime environmental damage, the ICC Statute, far from not going far enough on account of its restricted scope and effectiveness, actually goes too far.

The preamble of the ICC Statute speaks of ‘unimaginable atrocities that deeply shock the conscience of humanity’ and affirms that the ‘most serious crimes of concern to the international community as a whole must not go unpunished’.Footnote ¹⁹⁸ Some authors have even set out specific, numbered conditions that must be met before the violation of a norm is capable of becoming an international crime.Footnote ¹⁹⁹

Above, we saw how the ICC Statute provides a very broad definition of, among other things, crimes against humanity and war crimes over which the Court has jurisdiction. In discussing terrorism, one of the crimes not included in the ICC Statute, Professor Antonio Cassese, the first President of the ICTY, notes that the ICC Statute was intended only to include crimes that are, among other things, considered by the international community to be serious enough, in terms of their scale of effects and intensity, to warrant prosecution by an international tribunal.Footnote ²⁰⁰

However, a substantial portion of doctrine does not stop at a factual consideration of the seriousness of the violation. Many argue that more formalistic requirements must be met for a norm of international law, including of international humanitarian law, to be criminalized. In a separate publication, Cassese argues that, even for a ‘serious’ violation of international humanitarian law to become a war crime, it is necessary that there is proof that the violation has been criminalized by the jurisprudence of either relevant national courts or international courts and tribunals.Footnote ²⁰¹ René Provost argues that there must be consensus on the fact that the given breach will incur the individual penal responsibility of its author,Footnote ²⁰² while Georges and Rosemary Abi-Saab seem to go the farthest of all, by setting out an arduous double formation test akin to that generally considered to be necessary for the establishment of customary jus cogens norms:

These two authors, who appear to be desirous of maintaining the integrity of the international criminal law system, then go on to express concern that the drafters of the ICC Statute, who were appointed merely to set up an institution and not to codify substantial law, in fact promulgated the existence of war crimes beyond the scope of those established as criminal in customary international law.Footnote ²⁰⁴ The prohibition of wartime environmental damage is of course one prominent example of this phenomenon.

However, there are equal numbers on the other side, who consider it far from inappropriate that a group of national representatives may agree on provisions of international criminal law and have praised the ICC drafters' willingness to move faster than a customary international law to criminalize such acts as sexual offences and, of course, wartime environmental damage. For example, Provost argues that both the nature of environmental norms and the ineffectiveness of the state-responsibility-based regime to address the problem of wartime environmental damage justifies the criminalization of this prohibition,Footnote ²⁰⁵ while Steven Freeland is considerably more robust in his support for the criminalization of the norm, noting that the ICC was set up for the ‘deterrence and punishment of the most serious international crimes’ and then claiming that ‘[t]he deliberate destruction of the environment for strategic and military purposes, with its disastrous consequences for human populations, clearly falls within this description’.Footnote ²⁰⁶

The critical question is thus a matter of one's philosophy or, more precisely, one's frame of reference. In keeping with one of the key points made by this article, it is generally the authors looking at the provision from an environmental or international environmental law perspective who see no problem with the criminalization of wartime environmental damage, while those who approach it from a classical international law or international humanitarian/international criminal law perspective will question whether the ICC Statute's drafters really should have gone this far.

Indeed, given that criminal prosecution may be one of the best ways of ensuring compliance with many important norms of international humanitarian law, one should be careful not to detract too much from its integrity. A fledgling system depends on strong international consensus that its goals, approaches, and specific rules are appropriate. In the case of international criminal law, this would mean that all war crimes, which have imprisonment as their chief consequence,Footnote ²⁰⁷ should be sufficiently serious to warrant the major and politically controversial step of criminal prosecution of individuals in international courts. As Peter Sharp points out, ‘There is a compelling argument to be made for not pushing too far too fast in trying to turn the International Criminal Court into more than its language clearly states. One must conserve political capital for the most urgent battles.’Footnote ²⁰⁸

Given that the attacks in armed conflict causing widespread damage have only been prohibited in international humanitarian law since 1977 and do not appear to have yet crystallized into customary international law prohibitions, it would, in the present author's view, be inappropriate to suggest that all acts causing such damage should be subject to criminal prosecution. Indeed, most of the other violations criminalized by the ICC Statute, such as genocide, torture, and the taking of hostages, are well-established norms of customary law, which have even, in some cases, obtained the status of jus cogens. Returning to our scale of the seriousness of different international law violations, it is worth noting that many acts of terrorismFootnote ²⁰⁹ and the hostile use of nuclear weapons do not as such attract international criminal liability under the ICC Statute.Footnote ²¹⁰ While it may be debatable whether such acts should be considered as serious as wartime environmental damage in a contemporary world increasingly concerned about the degradation of the environment, such a comparison serves to show that, at least from an international humanitarian law perspective, the relevant criminal law provision analysed in detail above is perhaps justifiably narrow in its scope.

However, the contention that not all acts causing wartime environmental damage should be subject to prosecution in international criminal courts does not require as a corollary the view that no such acts should entail this consequence. Evidently, some intentional acts causing environmental damage in the context of armed conflict are significantly more serious, inexcusable, and therefore deserving of international criminal consequences for their perpetrators than others. When one considers both the growing international appreciation of the need to protect the natural environment and the fact that the prohibition of wartime environmental damage is still a relatively new phenomenon not yet established in the codex of customary international law, the international legal order is best served by settling for a compromise position that criminalizes only the most egregious intentional military acts causing significant damage to the natural environment.

Whether or not the ICC Statute correctly draws the line between those acts against the environment that are sufficiently serious to warrant criminalization and those that are not is something that can only be determined if and when we have jurisprudence from the ICC that authoritatively interprets the precise scope of Article 8(2)(b)(iv) of the ICC Statute. In the meantime, it is submitted on the basis of the analysis conducted in this article, that Article 8(2)(b)(iv) of the ICC Statute should not be criticized either for going too far by criminalizing wartime environmental damage or for not going far enough by imposing several demanding conditions that must be satisfied if a charge is to be sustained. Instead, one should appreciate that, when viewed from each of the two separate perspectives applicable to this matter – environmental law and the law of armed conflict – this limited, but nonetheless significant, step towards the criminalization of wartime environmental damage (as a corollary to existing, less demanding Additional Protocol I and ENMOD rules entailing the international responsibility of the offending state) may indeed strike the right balance between the need to protect the environment and the importance of maintaining the integrity of international humanitarian and international criminal law.