Managing the Fragmentation of International Climate Law

Abstract

This chapter focuses on the fragmentation of international law related to climate change and the interactions between the relevant legal regimes. It examines various management strategies with a view to enhancing synergies and mitigating conflicts between climate-related international legal regimes. The chapter starts with an overview of the ongoing debate on the fragmentation of international law. It then identifies the features of international climate lawmaking and implementation that constrain the usefulness of well-known legal techniques for avoiding and resolving conflicts. The chapter moves on to show how institutional cooperation between poli­tical bodies and bureaucracies may lead to enhanced coherence between the climate change regime and other legal regimes, while arguing that such a strategy will also encounter specific concerns related to their legitimacy. The chapter concludes by highlighting the need to apply various strategies for managing the fragmentation of international climate law, and identifies areas for further inquiry in this regard.

Harro van Asselt is a postdoctoral research fellow at the Stockholm Environment Institute. He is also a visiting research associate with the Environmental Change Institute at the University of Oxford and a visiting researcher with the Institute for Environmental Studies at VU University Amsterdam. The author would like to acknowledge funding from the European Commission (Intra-European Fellowship, CLIMATEGOV; contract 253090).

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1 Introduction

This chapter examines the international legal response to climate change by placing the United Nations climate regime in the context of the broader international regulatory environment. It aims to highlight the fragmented international legal order that is relevant for addressing climate change, and to suggest ways of managing interactions between the relevant international legal regimes. Building on the emerging body of literature on the fragmentation of international law, it discusses the opportunities for, as well as the limitations of, addressing the relationship between different areas of international law related to climate change through specific legal and institutional strategies.

The chapter proceeds from the assumption that it is not possible to find a single, comprehensive legal response to the problem of climate change. The rationale lies in the very nature of the problem – climate change can be conceived as a ‘wicked problem’ par excellence.¹ This means, among others, that there is no exclusive definition of what the problem is. Is the climate change problem, for instance, essentially about reducing greenhouse gas emissions, or phasing out fossil fuels, or is the problem more profound than that: Is it about the insistence on economic growth?² Similarly, there is no simple ‘solution’ to the climate change problem, as ‘solving’ the climate change challenge will depend on how one defines the problem in the first place. Any proposed solution will thus be influenced by one’s value judgement; actors promoting diverging values and ideologies are likely to advocate different responses to the climate change problem. Moreover, solutions to wicked problems like climate change may well have ripple effects, potentially causing new problems in their wake. Climate change is also characterized by specific traits that make it a ‘super’ wicked problem.³ First, the causes and impacts of, and responses to climate change cut across all sectors of the society. Various human activities and societal sectors contribute to the growing concentrations of greenhouse gases in the atmosphere. At the same time, the same activities and sectors may also be affected by the impacts of climate change. Second, climate change requires an urgent response if the goal is to avoid large-scale, irreversible impacts.⁴ Third, responding to climate change is complicated by the fact that international and national decision-makers cannot fully control the choices of actors that are relevant for addressing climate change.⁵ Fourth, climate change is a transboundary problem, and may indeed be “the greatest collective action problem the international community has yet faced.”⁶ This enhances tensions between countries, especially because those who are in the best position to take action have little incentive to do so.⁷ Fifth, climate change has an undeniable intertemporal dimension: to mitigate impacts in the future, action now is needed.⁸ Finally, the problem is characterized by various levels of scientific uncertainty, including uncertainty regarding the future development of greenhouse gas emissions as well as the impacts (and associated costs) of climate change in the long term.

By its nature, the climate change problem thus covers a broad range of narrowly defined issue areas, and its resolution inevitably requires a variety of responses. The implication at the international level is that issues relevant for the climate change problem are governed by a multitude of legal regimes with overlapping jurisdictions.⁹ For instance, the simple facts that some greenhouse gases are also ozone depleting substances, and that the substitutes for some of these substances are in turn greenhouse gases, inevitably means that the international legal regime for ozone layer depletion, notably the Vienna Convention for the Protection of the Ozone Layer¹⁰ and its Montreal Protocol,¹¹ is relevant for tackling climate change.¹² Similarly, because of the intricate connections between climate change mitigation and adaptation on the one hand, and biodiversity loss on the other, international biodiversity law, particularly the Convention on Biological Diversity (CBD)¹³ may affect the response to climate change, and may itself be affected by climate policies.¹⁴ Climate change and climate policy are also closely connected with economic activities, such as international trade and investment. Therefore, international economic law, including the law of the World Trade Organization (WTO), is of importance in the response to climate change.¹⁵ Furthermore, international climate law may interact with other areas of international law, including the law of the sea,¹⁶ human rights law,¹⁷ and the law on transboundary air pollution.¹⁸

In other words, international law on climate change is characterized by a certain degree of fragmentation. The phenomenon of regulatory fragmentation is clearly not limited to the issue of climate change. Indeed, over the past decade, fragmentation of international law has moved from the periphery to the centre of international legal debate. The increasing specialization of international law had already been noted by early observers in the 1980s,¹⁹ but discussions on the subject intensified at the turn of the millennium, when fragmentation was included in the work program of the International Law Commission (ILC).²⁰ The ILC released its report on fragmentation in 2006, providing an impressive overview of the various questions raised by the increasing specialization and diversification of international law.²¹ The report shows how conflicts may arise between special and general international law, as well as between different branches of international law, and reviews various legal techniques for avoiding and resolving conflicts of norms and regimes.²²

The ILC report points to possible tensions between different branches of international law, and recommends that “increasing attention will have to be given to the collision of norms and regimes and the rules, methods and techniques for dealing with such collisions.”²³ However, only a handful of the studies responding to this call have focused on international environmental law.²⁴ This is surprising, as the proliferation of international legal instruments is one of the key features of the development of international environmental law over the past decades. In 1993, Edith Brown Weiss already discussed the possible consequences of “treaty congestion” in international environmental law, identifying “operational inefficiency” as a key concern.²⁵ While the multiplication of international environmental agreements has certainly not been ignored in the period since, and has received particular attention in the context of discussions on reforming international environmental governance,²⁶ only limited attention has been paid to (the effectiveness of) strategies for managing the fragmentation of international environmental law.²⁷

Against this backdrop, this chapter aims to provide insights into strategies for managing fragmentation international climate change law by examining the potential of legal and institutional strategies with a view to enhancing synergy and mitiga­ting conflict between various legal regimes. The chapter is structured as follows: Section 13.2 provides an introduction to the debate on the fragmentation of international law. Section 13.3 identifies opportunities for, and limitations of, well-known legal techniques for avoiding and resolving inter-regime conflicts. Section 13.4 then moves on to show how institutional cooperation between treaty bodies created under different legal regimes may lead to greater coherence between the climate change regime and other international legal regimes. It argues, however, that such a strategy also raises concerns, especially regarding its legitimacy. Section 13.5 provides concluding remarks, and identifies areas for further research.

2 The Fragmentation of International Law

2.1 What Is ‘Fragmentation’?

‘Fragmentation’ means different things to different people. Indeed, the very use of the term has been the subject of a vigorous debate among international lawyers.²⁸ The discussions in the ILC and its 2006 report sparked a debate in international legal circles about the state of international law and governance, and about the potential threats and opportunities posed by the phenomenon of fragmentation.

The main reason why the term ‘fragmentation’ has caused so much controversy is its purported negative bias. Koskenniemi and Leino were among the first to point at a possible political agenda behind the use of the notion by several judges from the International Court of Justice (ICJ) at the turn of this century. They argued that the judges’ “postmodern anxieties” concerning the unity of international law could be best explained as an attempt to raise the profile of the ICJ on the international plane at a time when an increasing number of other judicial bodies might undermine its relevance.²⁹ Likewise, the fears that some authors have expressed about the growing specialization in international law have been explained as a counter-reaction of general international lawyers afraid of becoming irrelevant within their profession.³⁰ Yet, other terms such as ‘diversity’, ‘pluralism’, and ‘polycentricity’ have a positive subtext that would make them equally suitable to defend a certain position.³¹ For the purposes of this chapter, the term ‘fragmentation’ refers to a landscape where various international legal instruments are overlapping in terms of substantive issue coverage. This definition is intended to be value-neutral, and is primarily aimed at describing the state of international law relevant for addressing climate change.

To further clarify some of the conceptual confusion, two typologies of ‘fragmentation’ can be distinguished. A first distinction can be made between substantive and institutional fragmentation. The ILC made this distinction when it decided not to examine “the competence of various institutions applying international legal rules and their hierarchical relations inter se” (i.e. institutional fragmentation), but instead focused on “the splitting up of the law into highly specialized “boxes” that claim relative autonomy from each other and from the general law” (i.e. substantive fragmentation).³² Although the ILC study introduced this clear demarcation between substantive and institutional fragmentation, the two types are in fact inter-related. Abi-Saab describes this as a “law of legal physics”: “To each level of normative density, there corresponds a level of institutional density necessary to sustain the norms.”³³ This relation can also be seen in practice. For instance, the Swordfish dispute between the European Union and Chile is mostly seen as an example of institutional fragmentation, as the case was brought before the WTO dispute settlement mechanism and the International Tribunal for the Law of the Sea (ITLOS) simultaneously.³⁴ However, both dispute settlement mechanisms are inherently connected to substantive bodies of law, namely the various WTO Agreements and the United Nations Convention on the Law of the Sea (UNCLOS).³⁵

Second, the fragmentation of international law may refer to the relationship between different interpretations of general international law, the relation between general international law and specialized regimes, or the relations among two or more overlapping specialized regimes.³⁶ An example of the first type is the Tadić case, in which the International Criminal Tribunal for the Former Yugoslavia came to a different judgment about the criterion applicable to assess when an armed military group can be said to be acting on behalf of a foreign power than the earlier decision by the ICJ in the Nicaragua case.³⁷ Under the second category, scholars have discussed, for instance, how the general law on state responsibility relates to non-compliance mechanisms used in international environmental law or other more specialized regimes that may conflict with, or complement the general rules.³⁸ The third type of fragmentation is exemplified by the various trade and environment disputes before the WTO dispute settlement body, and forms the focus of this chapter.

2.2 The Promises and Pitfalls of Fragmentation

While the very notion of ‘fragmentation’ may thus reveal assumptions about its consequences, the positive and negative implications of fragmentation have been discussed extensively in the literature. This section draws in particular on the claims about the promises and pitfalls of fragmentation that have been raised in the international law literature, although it will also refer to other studies that have discussed the advantages and drawbacks of fragmentation in the specific context of global climate governance.³⁹

An ILC feasibility study on the fragmentation of international law conducted in 2000 indicated that the issue was one that should be looked at in terms mainly of “risks”, “threats”, or other negative connotations. In particular, it argued that fragmentation can be seen as detrimental, since “[d]oubts could be raised as to whether international law will be able to achieve one of its primary objectives, dispute avoidance and the stabilisation of international relations and, thus, achieve its genuine function of law. The credibility, reliability and, consequently, authority of international law would be impaired.”⁴⁰ This rather general statement can be split up in various arguments against fragmentation.

One argument is that the growing body of international legal rules threatens the unity and coherence of international law, as various specialized rules are created which allow international judicial institutions to reach diverging decisions, in other words, the institutional fragmentation referred to above.⁴¹ For instance, a dispute between Ireland and the United Kingdom regarding the construction of a plant reprocessing nuclear fuel led to three different legal procedures, all based on a different body of substantive law.⁴²Another important drawback is that the fragmentation of international law can be used by a handful of powerful States to their advantage. These States can opt for a mechanism that best serves their interests, and can create new agreements if the old ones no longer serve their interests.⁴³ With regard to dispute settlement, this may lead to ‘forum shopping’: countries are likely to choose the forum that is most likely to deliver a positive outcome. This explains why in the Swordfish dispute, the EU initiated proceedings at the WTO, arguing that Chile had restricted the movement of goods. Conversely Chile, the state taking conservation measures with respect to swordfish, brought its case before ITLOS, alleging that the EU had violated the law of the sea.

Finally, a fragmented international legal system could lead to (some degree of) prioritization of certain fields of international law over others, for example, the dominance of international economic law over international environmental law or – less likely – vice versa.⁴⁴ Indeed, such prioritization may be inevitable, as “each legal regime will naturally assert itself as the proper forum in which to address the situation, claiming superior status for its particular descriptions and concerns.”⁴⁵ Regimes, as Koskenniemi describes it, thus have a “structural bias” in favour of themselves.⁴⁶ This structural bias becomes important when one regime can be considered ‘stronger’ than others, because of the involvement of more powerful States, or because of stronger mechanisms to ensure compliance. This fear is often raised in the context of the trade and environment debate, where the WTO’s dispute settlement system is considered to be stronger than the non-compliance mechanisms of most multilateral environmental agreements.⁴⁷

While plenty of arguments thus draw attention to the negative effects of fragmentation, the literature shows that it may also entail numerous advantages. Indeed, after initial fears were expressed about the phenomenon, international legal scholars quickly realized that fragmentation might also have positive effects. First, fragmentation is viewed as a positive indicator of increased diversity in legal norms and the expansion of international law to previously unregulated fields.⁴⁸ Over time, international law has come to cover important new issue areas of international relations such as international commerce, human rights, and the environment. As Koskenniemi and Leino aptly put it: “Special regimes and new organs are parts of an attempt to advance beyond the political present that in one way or another has been revealed unsatisfactory.”⁴⁹ However, while the expansion to new areas could in principle be seen as a positive development, this does not necessarily mean that “more (international) law equals better (international) law.”⁵⁰

The increased specialization in international law is also arguably a way of accommodating diverging interests of States. As a result, governments view specialized regimes as better serving their interests and thus have stronger incentives to comply. As Hafner argues, a “less-than-global approach seems particularly necessary when different States clearly hold different beliefs about what basic values should be preserved by international regulation.”⁵¹ This argument has been reiterated in the context of international climate policy, where several observers have called for a ‘minilateral’ approach towards international decision-making on climate change.⁵² Furthermore, some commentators have posited that fragmentation would not endanger the coherence of the wider body of international law, as it would lead to the global diffusion of the “best ideas”.⁵³ Similarly, it has been argued that regulatory competition may allow for the development of different solutions in different regulatory contexts, of which the most effective will “survive” and be diffused to other regulatory contexts.⁵⁴

In summary, while the use – or non-use – of the term ‘fragmentation’ may serve particular agendas, my modest claim is that it provides an accurate description of the current state of international affairs, where the emergence of different social rationalities at the global level has led to multiple international agreements that overlap in terms of their subject matter. Whether the phenomenon is beneficial or malign is mainly in the eye of the beholder, and further depends on whether the term is used to describe the relationship between different specialized regimes or the relationship between such regimes and general international law. This chapter argues that the consequences of fragmentation do not necessarily depend on the existence of various overlapping agreements per se, but rather on how their inter-relationships are managed. To this end, the following sections provide an overview of the opportunities for, and limitations of, different legal and political strategies for managing the fragmentation of international climate change law.

3 Managing Fragmentation Through Legal Techniques

An international lawyer’s intuitive reaction to managing fragmentation is probably to resort to the rules provided by international law for dealing with norm conflicts. Indeed, the ILC report offers international lawyers a toolbox to address many of the challenges arising from the fragmentation of international law.⁵⁵ These tools include conflict avoidance techniques, such as treaty interpretation, as well as rules for deciding which treaty will prevail in case of a conflict, such as the maxims of lex posterior (i.e. the later treaty prevails) and lex specialis (i.e. the more specific treaty prevails). It is not my intention to review these various techniques here.⁵⁶ Instead, I will highlight some of the opportunities they provide for managing the fragmentation of international climate change law, as well as their inherent limitations.

3.1 Opportunities

3.1.1 Harmonious Treaty Interpretation

Treaty interpretation as a technique of avoiding a conflict between different climate-related treaties has been discussed in detail in the literature.⁵⁷ The ILC deemed Article 31.3(c) of the Vienna Convention on the Law of Treaties⁵⁸ a particularly promising avenue for avoiding conflicts,⁵⁹ and the provision has been the subject of an increasing number of analyses.⁶⁰ Article 31.3(c) provides that in the interpretation of treaties, “[t]here shall be taken into account, together with the context: … any relevant rules of international law applicable in the relations between the parties.”⁶¹ Like the other interpretation rules laid down in the Vienna Convention on the Law of Treaties, the provision is regarded to have the status of customary international law.⁶² Moreover, to some authors, the interpretative guidance contained in this provision amounts to a “principle of systemic integration” that forms “a constitutional norm within the international legal system,”⁶³ or a “principle of mutual supportiveness.”⁶⁴ Although there is a certain harmonizing appeal to the provision, no such principle has yet been explicitly recognized under general international law, and it still lacks an authoritative formulation.⁶⁵ Still, the notion finds some support in rules of treaty interpretation and also past case law, including decisions by the WTO dispute settlement system.⁶⁶ For instance, in the well-known US-Shrimp dispute, the WTO Appellate Body referred to the provision, indicating that it sought additional interpretive guidance from the general principles of international law.⁶⁷

The principle of systemic integration has been invoked as a possible tool to address (looming) conflicts between the UN climate regime and other legal regimes. For instance, in discussing a potential conflict between the Kyoto Protocol and biodiversity-related treaties, Pontecorvo argues that the principle confirms “a specific duty for Parties to interpret the provisions of the Kyoto Protocol relating to sinks potentially conflicting with pre-existing commitments under other treaties in such a way as to make them compatible with these commitments.”⁶⁸ It has also been suggested that the climate treaties (and decisions adopted under them) could be of use in the interpretation of other ambiguous or indeterminate WTO norms in case of a climate-trade dispute.⁶⁹ For instance, the climate treaties – and in particular a possible future climate agreement – could inform the analysis of whether a climate-related trade measure is “necessary to protect human, animal or plant life or health”⁷⁰ or “relating to the conservation of exhaustible natural resources”⁷¹ (emphasis added) under the general exceptions in Article XX of the General Agreement on Tariffs and Trade (GATT). A country adopting the measure could invoke the principle of systemic integration, and use its ratification of climate treaties in its defence of the non-commercial, environmental objectives of its measure. All other things being equal, participation in climate treaties would make the tests formulated in the exceptions of the GATT easier to meet.

It remains unclear whether Article 31.3(c) is indeed a “master-key”⁷² in dealing with fragmentation. First, it remains unsettled what “taken into account” actually entails.⁷³ It is generally agreed that this phrase does not mean that the extraneous rules override the interpreted rules, but rather that their normative significance needs to be determined on a case-by-case basis.⁷⁴ So while the legal norms developed under the climate regime could inform a decision by the WTO dispute settlement bodies, they could not result in the setting aside of WTO norms.⁷⁵ Second, while the provision has been invoked by international adjudicatory bodies,⁷⁶ some bodies, including the dispute settlement mechanism of the WTO, have been rather reluctant to seek recourse to it,⁷⁷ and it is far from clear whether they would do so in the future. Most notably, in the EC-Biotech Products dispute, the WTO Panel rejected the argument to consider the Cartagena Protocol on Biosafety to the Convention on Biological Diversity⁷⁸ as one of the “relevant rules of international law” under Article 31.3(c), because the membership of the treaty was not identical to the WTO.⁷⁹ If this approach was adopted, this would significantly limit the scope of Article 31.3(c) for avoiding conflicts between international legal regimes related to climate change, as parallel memberships of multilateral treaties are rather limited.⁸⁰ Third, and more importantly, the extensive academic debate on systemic integration ignores the fact that other methods for interpreting treaties already provide ample opportunity to take into account other rules of international law, and that Article 31.3(c) of the VCLT has mainly “residual value.”⁸¹ For example, a teleological interpretation of the provisions of the WTO Agreements, taking into account their “context” and their “object and purpose” would already include the preambular language on the WTO’s sustainable development objective,⁸² and would likely allow for a balancing approach which would not be too different from the one envisaged under Article 31.3(c). Furthermore, treaty interpreters may adopt an “evolutionary approach” irrespective of their reference to Article 31.3(c) of the VCLT.⁸³

The principle of systemic integration can thus be regarded as a strong integrative device in theory – but its theoretical strength is its weakness in judicial practice. Adjudicators will refrain from using it, as the resulting normative integration would also entail integration of authority – i.e. a direct influence on lawmaking.⁸⁴ As Broude explains, “to integrate (with) the norms of another system is to acknowledge the authority of that other system to produce pertinent norms” as well as “assert[ing] authority over them.”⁸⁵ It is this integration of authority that dispute settlement bodies seek to avoid by using ‘weaker’ forms of integration, such as Article 31.1 of the VCLT.⁸⁶ Similarly, while a possible “principle of mutual supportiveness” has much theoretical appeal as an interpretative device,⁸⁷ it cannot be automatically inferred that it would be used in practice.

3.1.2 Conflict Clauses

In case a conflict between two different treaties arises, the starting point for its resolution is to examine whether a treaty contains any conflict clauses.⁸⁸ The purpose of such clauses is to clarify the relationship between treaties, and to prevent contradictions.

The climate treaties contain several provisions that regulate their relationships with other multilateral agreements and international organizations. For instance, the United Nations Framework Convention on Climate Change (UNFCCC)⁸⁹ and the Kyoto Protocol⁹⁰ delimit their scope by only covering “greenhouse gases not controlled by the Montreal Protocol.”⁹¹ While this provision shows awareness of the linkages between the problems of – and solutions to – climate change and ozone layer depletion, it does not in itself prevent or resolve conflicts between them.⁹² It can also be argued that the Kyoto Protocol’s reference to “relevant international environmental agreements” in Article 2.1(a)(ii) constitutes a conflict clause, with a view to ensuring that parties to the Protocol do not implement climate policies that frustrate the objectives of other environmental treaties. The provision requires that in implementing and elaborating climate change policies and measures, developed countries take into account their commitments under “relevant international environmental agreements.”⁹³ However, the provision is unclear about which commitments in other agreements it refers to, and also merely states that such commitments should be “taken into account” by parties.⁹⁴ It is thus difficult to see how this formulation could be construed in such a way that it would subordinate the commitments in the Kyoto Protocol to other international environmental agreements.⁹⁵ Article 3.5 of the UNFCCC and Article 2.3 of the Kyoto Protocol could also be seen as conflict clauses with respect to the WTO agreements. Article 3.5 of the UNFCCC provides, inter alia, that “[m]easures taken to combat climate change, including unilateral ones, should not constitute a mans of arbitrary or unjustifiable discrimination or a disguised restriction on international trade.”⁹⁶ Under Article 2.3 of the Kyoto Protocol, developed countries must “strive to implement policies and measures… in such a way as to minimize adverse effects, including the adverse effects of climate change, effects on international trade, and social, environmental and economic impacts on other Parties…”⁹⁷ However, these provisions do not establish a clear hierarchy between the trade and climate change regimes, and do not – explicitly or implicitly – allow or prohibit climate-related trade measures.⁹⁸ In other words, they do not determine which treaty would prevail in case a conflict arises. Still, it is important to also note what the agreements do not explicitly state: they do not subordinate to the WTO Agreements, in contrast with, for instance, the Cartagena Protocol on Biosafety;⁹⁹ and they do not explicitly allow for trade measures against non-parties or non-compliers.¹⁰⁰ Furthermore, while not being explicit conflict clauses, the provisions may still provide interpretative guidance. For instance, it can be argued that Article 2.3 of the Kyoto Protocol directs Parties to adopt measures that minimize effects on international trade, except in cases where such effects are necessary to ensure the effectiveness of such measures.¹⁰¹ Finally, the Kyoto Protocol contains a provision delimiting the scope of the climate treaties by delegating the negotiation of rules on emissions from international aviation and maritime transport to the International Civil Aviation Organization and the International Maritime Organization.¹⁰²

Other climate-related treaties contain more clearly identifiable conflict clauses. For instance, the CBD gives priority to any existing agreement, “except where the exercise of those rights and obligations would cause a serious damage or threat to biological diversity.”¹⁰³ This clause arguably serves to limit climate change mitigation activities that would cause a serious damage or threat to biodiversity.¹⁰⁴ However, it applies only to treaties existing at the time of the CBD’s adoption in 1992, and is thus not applicable to the Kyoto Protocol, adopted in 1997. Furthermore, the phrase “serious damage or threat to biological diversity” is nowhere defined or elaborated upon, meaning that the practical application of the clause remains uncertain. It is therefore “doubtful that this clause can prevent or solve conflicts.”¹⁰⁵ Article 311.3 UNCLOS is also a provision that claims priority over any other international agreement incompatible with it.¹⁰⁶ Consequently, if, for example, certain forms of geological carbon storage were inconsistent with UNCLOS, but were endorsed under the UNFCCC umbrella, this clause could be called upon to argue that UNCLOS prevails over the climate treaty.

There are various difficulties with the use of conflict clauses: their wording is often unclear and open to diverging interpretations (e.g. what would establish “a serious damage or threat to biological diversity”?); they are not dynamic enough to reflect new developments (e.g. changes in scientific insights); it is not always clear when a treaty comes into existence;¹⁰⁷ and chances are that such clauses may never be applied “in the absence of a single, unifying dispute settlement system.”¹⁰⁸ Nevertheless, from a legal perspective, they provide the primary means for addressing the relationship between treaties. An opportunity for managing fragmentation thus lies in their drafting. Whenever a new treaty or amendment is negotiated – either within the UNFCCC context or outside of it – conflict clauses could be drafted in a way that fully considers the implications for other treaties, and preferably in an unambiguous manner.¹⁰⁹ Hence, making a list of all international legal instruments that may have an impact on the treaty under negotiation is sensible.¹¹⁰ Under such a “stop and think approach” the impacts of a new treaty or a treaty amendment would be carefully assessed, where appropriate, in cooperation with the relevant states, secretariats and international organizations.¹¹¹ This suggestion is certainly not new. In 1953, Jenks already noted the importance of consultations before and during the drafting of legal instruments.¹¹² However, there is as of yet still no standard procedure to assess the impacts of a new instrument on existing ones, or to consider how an instrument could contribute to the objectives of other treaties. An opportunity thus lies in introducing such a procedure in drafting new climate-related agreements.

3.2 Limitations

3.2.1 Definitions of ‘Conflict’

Whether international law can play a role in resolving conflicts between the climate treaties and other agreements depends on whether a conflict – in the strict legal sense – actually exists. This may sound like a clear-cut exercise, but is everything but that. Indeed, the scholarly literature is divided on the issue, with some authors arguing for a ‘narrow’ definition, and others opting for a ‘wide’ definition.¹¹³ The main challenge in defining conflicts is to capture the divergences between different legal regimes, while at the same time acknowledging that not all divergences need to be resolved through the establishment of a hierarchy between the relevant regimes.

According to the classical definition suggested by Jenks, a “conflict in the strict sense of direct incompatibility arises only where a party to the two treaties cannot simultaneously comply with its obligations under both treaties.”¹¹⁴ More recently, this test of ‘impossible joint compliance’ has become the subject of criticism.¹¹⁵ In particular, critics argue that Jenks’ focus on obligations only is too limited, and unjustifiably excludes incompatibilities between obligations and permissions. This would include cases of overlap in which a (future) climate change treaty permits a measure that restricts international trade, whilst a trade agreement contains a specific obligation not to restrict trade. Addressing this lacuna, Pauwelyn’s treatise on the conflict of norms in international law includes a proposal to expand the definition to include conflicts involving permissive norms. Vranes similarly argues for a broader definition, which comprises “incompatibilities between permissions and obligations, permissions and prohibitions, and obligations and prohibitions,” adding that there is a conflict if one of the norms “is necessarily or potentially violated.”¹¹⁶

Jenks already acknowledged that his narrow definition might not cover all the divergences and inconsistencies between treaties that may have negative effects.¹¹⁷ While the wider definitions proposed by Pauwelyn and Vranes ensure that certain obvious conflicts are not “defined away,”¹¹⁸ even their construction of conflict may be insufficient to cover the various kinds of incompatibilities that may arise in international climate law (and, arguably, in international law more broadly). In this regard, Wolfrum and Matz identify several categories of conflicts in international environmental law that fall outside the aforementioned definitions.¹¹⁹ These include, in the first place, conflicts between agreements resulting from their different objectives (e.g. trade liberalization versus environmental protection). The broader categorization also includes conflicts arising from the incorporation of different principles and approaches (e.g. a precautionary approach versus cost-effectiveness). Differing objectives and principles, however, do not necessarily need to lead to conflicts between two treaties, especially where they are phrased in unclear terms. It is especially in the instances where States have a wide margin of discretion that there may be a conflict in the implementation phase of the agreements.¹²⁰ In the case of international law on climate change, this is evidenced by the triggering of conflicts through decisions of treaty bodies, as will be discussed below.

It can thus be established that even wide legal definitions of ‘conflict’ seem to be insufficient to cover all potential climate-related conflicts. But here it should be asked: insufficient for what purpose? This is perhaps the most crucial question regarding the definition of conflicts, and it is emerging as a focus in the debate on the fragmentation of international law.¹²¹ In this regard, it is useful to cite one of Vranes’ main objections to a narrow definition: “The problematic consequence … is that conflicts maxims such as the lex posterior principle cannot come into play …  .”¹²² In other words, it is important to establish that there is a conflict if one wishes to decide which norm prevails. But this is based on an assumption that one of the norms should prevail, or that the existence of a conflict in a particular situation is undesirable. Such an assumption can be explained through the ‘structural bias’ of a specific regime: from a climate change perspective, climate-related norms should trump trade norms. From the trade perspective, trade norms should naturally prevail.¹²³ This assumption can be questioned if it is accepted that two legal regimes can pursue a similar objective, such as the pursuit of sustainable development,¹²⁴ or if one seeks to identify an otherwise overarching ‘narrative’ that reconciles two regimes.¹²⁵ In other words, is it really desirable that a hierarchy between norms be established? This seems to be purpose of most conflict resolution techniques discussed by the ILC, such as the lex specialis and lex posterior rules, and conflict clauses. However, if one accepts that the climate regime and related regimes are actually pursuing common goals, this quest for normative hierarchy becomes rather futile.

3.2.2 Treaty Body Decisions

The climate regime, like many other international environmental regimes, is characterized by a form of lawmaking that departs from the traditional idea of treaty-based lawmaking. Lawmaking does not stop when the treaty text is agreed upon, but continues through the decision-making bodies constituted by those treaties, such as the Conference of the Parties (COP) established under the UNFCCC. The consequence of this innovative form of international lawmaking is that interactions between international legal regimes could well be ‘triggered’ by a decision by a treaty body rather than the treaty itself. In fact, the impacts of rule-development on forest carbon sinks under the Kyoto Protocol on issues discussed under the CBD shows that the potentially conflicting interaction has its origins in the decisions made by the UNFCCC COP,¹²⁶ as it is those decisions that allow for the implementation of Clean Development Mechanism projects that might result in adverse impacts on bio­diversity.¹²⁷ Yet the debate on the fragmentation of international law is primarily concerned with conflicts stemming from treaties as such. This is in line with the aforementioned discussions on conflicts in international law, which have tended to focus primarily on treaties as the source of conflict. For instance, the classic definition by Jenks states that a “conflict in the strict sense of direct incompatibility arises only where a party to the two treaties cannot simultaneously comply with its obligations under both treaties” (emphasis added).¹²⁸ In addition, various legal techniques to avoid or resolve conflicts are based on, or linked to, the law of treaties. This means that the question of how to deal with cases where the texts of two treaties are perfectly compatible, but subsequent rule-development under one of the treaties leads to a conflict has thus far been largely ignored.

Whether such situations are captured by the ongoing fragmentation debate depends on the legal status assigned to the decisions of the treaty bodies of international environmental agreements. In other words, to what extent do the decisions adopted by these bodies constitute international lawmaking in a traditional sense?¹²⁹ There is no straightforward answer, but it has been argued that while COP decisions are not devoid of normative substance, their legal force is intrinsically connected to the treaty obligation upon which they are based. As Wiersema concludes: “consensus-based COP activity … cannot be seen as giving rise to stand-alone legal or even political obligations” and COP decisions “hold little meaning but for their connection to the treaty.”¹³⁰ However, even if it can be successfully argued that there are intricate linkages between COP decisions and underlying treaty provisions, this does not mean that the decisions themselves are covered by the law of treaties.¹³¹

The increasing relevance of decisions by treaty bodies in international environmental lawmaking hence limits the usefulness of the conventional conflict resolution techniques. This does not mean that any conflicts arising from such decisions cannot be dealt with, but rather points to the need to think about alternative means to manage them.

4 Managing Fragmentation Through Institutional Cooperation

While legal techniques hold some potential to manage the fragmentation of international climate change law, particularly in the case of normative conflicts, their limitations are also clear. This realization has directed attention towards less formal approaches to managing fragmentation. In particular, the question has been raised to what extent treaty bodies, such as COPs and secretariats, could enhance coherence between different legal regimes. Again, I do not seek to provide an exhaustive overview of options for institutional cooperation, but rather focus on the most pertinent opportunities and limitations of this particular management strategy.

4.1 Opportunities

4.1.1 Bureaucracies

Bureaucracies, such as the UNFCCC Secretariat, are important actors in international environmental – and climate change – governance, yet they have largely flown under the radar of analysts. They can be regarded as key actors ‘behind the scenes’ in managing the fragmentation of international climate law. However, although their influence on the individual regimes they are tied with is becoming clearer,¹³² their role in managing the relationships between different regimes remains under-researched.¹³³

Whether there is a mandate for secretariats to engage in institutional cooperation is not the same question as whether these secretariats have the legal capacity to enter into external cooperation agreements in the first place. The latter question has been examined in-depth by Churchill and Ulfstein, who conclude that the institutions of multilateral environmental agreements “have implied powers to act on the external plane, including the capacity to enter into treaties when necessary to carry out their functions.”¹³⁴ Specifically with respect to secretariats, Chambers argues that while the legal personality of secretariats may not be entirely clear, their power “would certainly include entering into agreements of collaboration with other [multilateral environmental agreements] where there is a clear overlap or interest.¹³⁵

In terms of mandates, liaising with other secretariats is generally one of the tasks assigned to the secretariats of environmental treaties. This is the case, for instance, for the climate secretariat,¹³⁶ the ozone secretariat,¹³⁷ and the biodiversity secretariat.¹³⁸ Although cooperation is not explicitly included in the mandate of the WTO Secretariat, it has become active in enhancing the transparency of the WTO’s activities related to climate change,¹³⁹ for instance, through the organization of side-events at COPs and the publication of reports on the linkages between trade and climate change.¹⁴⁰

Institutional cooperation between the climate secretariat and other bureaucracies has remained largely limited to observership, mutual attendance at meetings, scientific cooperation, and information exchange. An interesting development in this regard has been the formation of the Joint Liaison Group, which comprises the secretariats of the CBD and the UNFCCC, subsequently also joined by the secretariat of the UN Convention to Combat Desertification (the third ‘Rio Convention’).¹⁴¹ The mandate of the Joint Liaison Group is to “enhance coordination between the three conventions, including the exchange of relevant information” and “[t]o explore options for further cooperation between the three conventions, including the possibility of a joint work plan and/or a workshop.”¹⁴² By the end of 2011, the Joint Liaison Group had convened ten times, focusing on crosscutting issues such as research and monitoring, information exchange, technology transfer, capacity building, financial resources, education and public awareness, and adaptation to climate change. Its activities primarily consist of information exchange and coordination between the administrative bodies of the different regimes.¹⁴³ In 2004, the three secretariats drafted a joint paper identifying options for enhanced cooperation. Whereas some of the options identified in the paper (for instance, joint workshops or the sharing of information among secretariat staff) are relatively easy to implement, others (such as the harmonization of reporting) require much more preparation and consensus.¹⁴⁴

There may be opportunities for enhancing the role of the secretariats in promoting synergies between different environmental regimes. For instance, the tool of memoranda of cooperation – widely used, for instance, by the biodiversity secretariat – has rarely been used by the climate secretariat. Such written agreements could formalize existing informal practices, thereby keeping the relationship with other regimes permanently on the agenda. However, it can be questioned whether formalizing cooperation per se would result in synergies at the operational level. Indeed, one of the advantages of the secretariats’ activities is that they avoid the cumbersome political decision-making processes of the COPs, and thereby provide a valuable informal and flexible way of integrating environmental regimes.

4.1.2 Decision-Making Bodies

While the bureaucracies of environmental treaties thus may play an important role in raising awareness of interactions and their consequences, they do not have any decision-making competencies. Nevertheless, also the decision-making bodies in environmental treaties are often guided to cooperate with other bodies. In this regard, the decision-making bodies of the climate regime are mandated to “[s]eek and utilize, where appropriate, the services and cooperation of, and information provided by, competent international organizations and intergovernmental and non-governmental bodies.”¹⁴⁵ Other environmental conventions contain similar instructions. The Vienna Convention on Ozone Layer Depletion directs its parties (and parties to subsequent protocols adopted under the treaty) to cooperate with competent international bodies.¹⁴⁶ Likewise, the CBD COP is mandated to “[c]ontact, through the Secretariat, the executive bodies of conventions dealing with matters covered by [the CBD] with a view to establishing appropriate forms of cooperation with them.”¹⁴⁷ This has formed the basis for the cooperation between the biodiversity secretariat and other secretariats mentioned above. Also in the area of the international trade regulation, the Agreement Establishing the WTO provides that the “General Council shall make appropriate arrangements for effective cooperation with other intergovernmental organizations that have responsibilities related to those of the WTO.”¹⁴⁸ It thus seems clear that there is ample scope for decision-making bodies to cooperate with each other.

Not every decision-making body is equally active, however. In particular, the UNFCCC COP has been rather silent about its relationships with other inter­national conventions. There has been only one COP decision on cooperation, which generally affirms the need for enhanced cooperation “with the aim of ensuring the environmental integrity of the [Rio Conventions] and promoting synergies under the common objective of sustainable development, in order to avoid duplication of efforts, strengthen joint efforts and use available resources more efficiently.”¹⁴⁹

In contrast, decision-making bodies of other international environmental regimes have sought to manage the overlap with the climate regime. For instance, the CBD COP has adopted a wide range of decisions related to climate change and biodiversity, which have been instrumental in highlighting biodiversity concerns in UNFCCC decisions,¹⁵⁰ although they have not necessarily lead to stronger references to bio­diversity protection in the climate regime’s decisions. The parties to the Montreal Protocol have also been engaged in activities closely related to the climate regime, most notably by adopting a decision in 2007 that significantly accelerated the phasing out of the consumption and production of hydrochlorofluorocarbons, a potent greenhouse gas that also served as substitute for ozone depleting substances.¹⁵¹ A similar decision to limit the use of another substitute with global warming potential, hydrofluorocarbons, has been proposed by some parties to the Montreal Protocol, but is still opposed by others.¹⁵²

While institutional cooperation on climate-related overlaps between regimes thus mainly takes place unilaterally – initiated mainly by several proactive decision-making bodies outside the UNFCCC – enhanced cooperation could take place in a “more ambitious form of comprising joint planning of programmes or even the coordination of substantive decision-making or implementation activities.”¹⁵³ There are examples of such enhanced cooperation in international environmental law, for instance, in biodiversity protection, fisheries management and chemical substances.¹⁵⁴ In the case of chemicals, it was even possible to hold a joint session of the decision-making bodies of three different multilateral environmental agreements. Although extending this type of institutional cooperation to the climate regime may sound attractive in theory, there are limitations to what is possible and desirable, as will be discussed in the next section.

4.2 Limitations

4.2.1 Unclear Mandates

Although institutional cooperation to manage linkages between the climate regime and other legal regimes is intensifying, the effects are as of yet uncertain. While institutional cooperation can create mutual awareness between regimes, and build capacity at various levels, it is often also plagued by rhetoric about the ‘mutual supportiveness’ of different treaties, and devoid of practical suggestions. Part of the reason for this is that institutional cooperation is challenging because of unclear or restricted mandates.

Secretariats initiating cooperation with other bodies usually act upon a decision by the COP, thereby interpreting the mandate provided in such a decision. While it may seem “commonsensical that a secretariat would not engage in activities against the will of its member states,”¹⁵⁵ it is actually not always clear what this ‘will of the parties’ is. In other words, secretariats do not always have a clear legal authority regarding the extent of institutional cooperation.¹⁵⁶ This may either constrain or enable them. Parties often tend to interpret the secretariats’ mandates restrictively, and secretariats will need to walk on eggshells when engaging in activities with other international actors. This is especially the case for the UNFCCC Secretariat, which has been said to be “living in a straitjacket” imposed by the parties.¹⁵⁷ However, other secretariats have taken a more proactive stance by adopting a wide interpretation of their mandate. The CBD secretariat, for instance, has made use of the limited space provided to it by the COP, partly due to a very active Executive Secretary.¹⁵⁸

Cooperation between secretariats is even more difficult if their respective mandates differ in their scope. For instance, at its fifth meeting, the Joint Liaison Group argued for consistent guidance from the various COPs, indicating that it can only facilitate, but not guarantee such consistency.¹⁵⁹ Furthermore, at its ninth meeting, the Group noted that “there remains a disconnect between the roles and mandates given to the [Joint Liaison Group] by each convention with this disconnect resulting in limitations when considering the implementation of the requested activities.”¹⁶⁰ Because of these limitations, the Joint Liaison Group acts primarily as a forum to facilitate information exchange, and to encourage harmonizing implementation of the Rio Conventions at the national level.¹⁶¹

4.2.2 Overstepping Regime Boundaries

The mandate for cooperation – and how it is interpreted – will, for an important part, depend on parties’ willingness to construct linkages with other regimes. This brings us to one of the core challenges to enhancing institutional cooperation: the risk that states “may be unwillingly drawn into regimes that they are not party to or affiliated with, and implicitly become subject to obligations under those regimes, by virtue of cooperative arrangement.”¹⁶² It can be assumed that any effort by actors in one regime to influence the normative development in another will likely be limited by the extent to which memberships are congruent. For instance, while the United States is a party to the UNFCCC, it has not ratified the CBD. A broad mandate for the climate regime’s treaty or administrative bodies to cooperate with the CBD could lead to the perception that state sovereignty is eroded by “importing” concepts or rules from the CBD.¹⁶³ Party submissions to the UNFCCC seem to confirm that this perception exists. Responding to the work of the Joint Liaison Group in 2004, the United States noted that the Rio Conventions “have a distinct legal character, mandate and membership.”¹⁶⁴ Australia even argued that “[t]he CBD and the UNCCD do not have a legitimate role in greenhouse mitigation, which is clearly the work of the UNFCCC.”¹⁶⁵ But even when membership is largely overlapping, there may be resistance to the idea of cooperation between bureaucracies. For instance, with respect to the WTO secretariat’s role in managing the climate-trade overlap, Cossy and Marceau note that “the competences of the secretariats are limited (they do not normally include decision-making) and underlain by their obligation to remain neutral vis-à-vis the membership.”¹⁶⁶

More generally, cooperation between institutional arrangements of two different regimes gives rise to concerns about legitimacy and accountability.¹⁶⁷ If one adopts a more traditional legal perspective emphasizing the importance of state consent (and state sovereignty) in international lawmaking, it is difficult to see where the legitimacy of enhanced institutional cooperation comes from, particularly in the case of incongruent memberships. These concerns relate back to the ‘structural bias’ of each regime.¹⁶⁸ Can cooperation really take place in a fashion that gives equal weight to the norms of each regime? This may not be the case when ‘stronger’ and ‘weaker’ regimes are concerned. This could result in the prioritization of one regime over another, meaning that cooperation “may become dominated by procedures, principles and concepts that are prevalent within one regime at the expense of [others].”¹⁶⁹ Another matter is whether the norms of each regime should be given equal weight. Young argues convincingly that bodies seeking to cooperate with other regimes should “scrutinise and review the ‘sources’ of external regimes.”¹⁷⁰ Only in this way, she posits, can institutional cooperation be made accountable, and can the risk of ‘managerialism’ be avoided.

5 Concluding Remarks

The ‘wicked’ nature of the climate problem means that it is difficult, if not impossible, to govern the problem through a single legal regime. The argument here is that any effective response to the climate change problem will need to take into account the potential of other regimes to either mitigate or exacerbate the problem, while at the same time also considering the impacts of the climate regime on other legal regimes. International climate change law is thus inevitably fragmented. However, the consequence of such fragmentation does not have to be regulatory chaos, or the prioritization of one policy field over another – as has been feared by international lawyers participating in the general debate on the fragmentation of international law. Crucially, the implications of the fragmentation of international climate law depend on how it is managed.

With this in mind, this chapter has sought to illustrate the potential of well-known legal techniques to manage interactions between different international legal regimes. It has also addressed several less-well studied forms of institutional cooperation. With respect to legal techniques this chapter argued, first, that pursuing harmonious treaty interpretation, whereby treaty interpreters take into account extraneous rules, could avoid conflicts between climate-related treaties. It questioned, however, whether this necessarily needed to take place through a principle of ‘systemic integration’ or ‘mutual supportiveness’, which some scholars have suggested is embodied in Article 31.3(c) of the VCLT. Second, it indicated that in the course of international climate lawmaking, negotiators could take a step back, carefully considering the implications of the negotiations for other regimes and drafting provisions to regulate their inter-relationships. The chapter then moved on to point out that many of the tensions involving the climate regime cannot be adequately be captured by traditional legal definitions of conflict thereby limiting the usefulness of many techniques discussed in detail by the ILC. Furthermore, it questioned whether applying such techniques – leading to a normative hierarchy – is in fact desirable at all.

This chapter argued that informal institutional cooperation can complement the formal legal techniques for managing the fragmentation of international climate law. It showed how various secretariats as well as decision-making bodies in climate-related regimes have started to address overlapping issues, with a view to avoiding conflicts and maximizing synergies. However, it is clear that there are also limitations as to what can be achieved through such means. Secretariats’ mandates are not always clearly defined, and to avoid a rebuke by parties, secretariats will tend to stay away from intruding too much into the decision-making process through external cooperation with other institutions. This question is linked with more general concerns about the legitimacy and accountability of institutional cooperation. These concerns are to some extent based on traditional notions of state consent, but they point to the real risk that actors in one regime are sidelined through the use of norms borrowed from another.

Although this chapter has given a first indication of how the fragmentation of international climate law could be managed, further research into the (im)possibilities of other strategies could complement the existing body of knowledge. First, the focus of this chapter has been on the international level. It should, however, be clear that managing the relationship between different regimes, to an important extent, takes place at the national or subnational level – i.e. in the implementation phase of international agreements. While the coordination and integration of policies and laws has been the subject to attention of lawyers and political scientists at the domestic level, further research could shed light into the way in which such coordination could strengthen the coherence of international law. Vice versa, there has been little research on how cooperation at the international level could strengthen coherence in the implementation phase. Second, and related to the first point, there has been scant attention to the role of non-state actors, such as environmental organizations, the private sector, or public-private partnerships, in improving mutual coherence between different regimes. A third point relates to the legal form of international climate governance. While international legal instruments, including the climate treaties, other environmental treaties, and international trade law, still play a key role in steering behaviour, climate governance is characterized by the emergence of a wide array of non-state initiatives, and initiatives that could be rather regarded as soft law. The point here is that the role of legal techniques for managing the fragmentation of international climate law may further diminish if the role of international law in addressing climate change itself is further reduced. Indeed, the Vienna Convention on the Law of Treaties or conflict resolution principles such as lex specialis will not be applicable in case of interactions between hard law and soft law, since there will not be any norm conflict in the strict legal sense. The relationship between hard and soft law related to climate change, and the management of their relationship is therefore another appropriate area for further inquiry.