The climate in Strasbourg – the judgments and their impact on global climate law

Abstract

The judgments of the European Court of Human Rights in April 2024 represent the Court’s first foray into climate change law. The climate has been the source of much regulation in international law and litigation across the world has proliferated since the 2015 Paris Agreement. How, then, does the Court engage with the specialized regime of the Paris Agreement and UNFCCC in its recent jurisprudence? Is there a potential for this judgment to have an impact on the interpretation of international climate law? The KlimaSeniorinnen judgment is perhaps the most authoritative case of international climate change litigation to date, and has the opportunity to influence the consideration of reoccurring themes in climate litigation. This article will lay out the interaction and potential impacts of these judgments on international law, as well as climate change litigation. It will show that the Court has concretized the position of the Conference of the Parities to the Paris Agreement as a strong, normative influencer in the climate change regime, and the role of courts as protectors of human rights against the adverse effects of climate change is vital.

1. Introduction

Instances of climate change litigation have increased globally since the adoption of the Paris Agreement. ¹ In such instances, courts have been petitioned to review governmental climate policies and plans in light of, inter alia, national constitutional law, national statutes, international climate change law and international human rights instruments. Taking an overview of international jurisprudence on climate law, common themes which transcend jurisdictions and fora can be observed, such as the use of scientific evidence in decision-making, the justiciability of questions related to climate change and questions related to burden sharing and carbon budgets. This contribution aims to review the recent climate jurisprudence of the European Court of Human Rights (ECtHR or the Court) in light of such common themes, reviewing reoccurring questions that arise in global climate litigation, specifically the role of Courts in the tackling of this looming threat, and how the Court engages with the international climate change regime. This contribution will argue that in its decisions, the Court implicitly solidified the position of the Conference of the Parties to the Paris Agreement (CMA, or COP when referring to the treaty body of the United Nations Framework Convention on Climate Change) as a body which goes beyond mere political cooperation and implementation review, and as far as developing the obligations within the Agreement itself.

On 9 April 2024, the Court handed down two decisions, Carême v. France ² and Duarte Agostino and others v. Portugal and others, ³ and one judgment, Verein KlimaSeniorinnen Schweiz and Others v. Switzerland, ⁴ all of which have been referred to as landmark, vital and historic. ⁵ These decisions have also been the subject of significant academic attention. ⁶ This trio of cases represents the first occasion on which the Court recognized that climate change impacts not only on the planet as such, but also the rights spelled out in in the European Convention on Human Rights (ECHR or the Convention). In particular, the KlimaSeniorinnen case affirmed that States Parties have a positive obligation to adopt appropriate measures to combat climate change. The Court read this clarification through the lens of the existing climate change law regime, specifically the Paris Agreement and the United Nations Framework Convention on Climate Change (UNFCCC), as well as the latest scientific evidence of the Intergovernmental Panel on Climate Change (IPCC). In the April rulings, the Court considered a multitude of climate change-related questions, such as, inter alia, issues of standing of individuals and associations and of extraterritoriality, and also introduced a new margin of appreciation for Article 8 ECHR.

As mentioned previously, the present contribution will focus on the Court’s consideration of a number of interrelated and ‘classic’ questions which arise in global climate litigation. The overarching aim of this contribution is to examine and review the Court’s engagement with international climate change law, thereby highlighting the Court’s stance on several specific issues, including the issue of extraterritoriality, the temperature target of the international climate change law regime and the position of courts in the complicated governance of climate change.

In examining the potential novelty of the Court’s reasoning, its approach to the international climate change regime will be reviewed and placed in the broader context of its interpretive approaches to other international law sources. In addition, the Court’s appreciation of the role of courts and judicial review in the context of climate change will be reviewed. This issue has been treated differently in similar contexts, and the Court provided important guidance that has the potential to be replicated in other fora. This analysis is of particular pertinence in view of the fact that the Court’s rulings represented one of the first examples of an international court giving an international perspective to the national constitutional law question of the role of courts in the context of climate change.

Each of the three cases before the Court, albeit to varying degrees, discussed international law. However, with both the Carême and the Duarte Agostino cases having been declared inadmissible, these decisions are of less interest in the study of the development of the international framework for the obligations of climate change. The focus of this contribution will be on the KlimaSeniorinnen case, and specifically on those aspects of the case which have a probable impact on the larger international framework. First, however, the Duarte case will be reviewed, with attention given to the Court’s appreciation of extraterritoriality.

2. The Duarte case

A. Dispute at hand

The Duarte case was brought by six young applicants from Portugal, alleging breaches of Articles 2, 3, 8 and 14 ECHR, ⁷ due to the present and future impacts of climate change. The claimants alleged that the impacts of climate change, such as heatwaves and wildfires, were the result of inadequately ambitious mitigation measures foreseen by Portugal and the 32 other respondent states named in the application. The case was found to be inadmissible. The application against Portugal, which was territorial in scope within the meaning of Article 1 ECHR, failed because the applicants did not exhaust domestic remedies. The applicants claimed that the Court should adopt new standards on extraterritoriality with regard to the other respondent states. The decision on admissibility therefore centrally examined whether the respondents (other than Portugal) could be held responsible for climate-related impacts resulting from emissions originating within their territorial jurisdictions, where the harm in question was felt extraterritorially to the origin of the emissions.

B. The Court’s assessment: Extraterritoriality and climate change

Under the ECHR, a state has the obligation to secure the rights of those within its physical borders, and therefore only to those within its territory, unless an exception applies. ⁸ Jurisdiction under the ECHR is thus inherently territorial, and the exceptions are strict . These are instances where jurisdiction applies extraterritorially, therefore outside the physical territory of a state, but still within the scope of protection of the Convention.

These exceptions include instances where there is de facto control of a state over a foreign territory, ⁹ or when state agents exercise authority and control over individuals, through physical power and control or proximate force, outside the territory of said state. ¹⁰ Finally, a third ‘jurisdictional link’ category of extraterritoriality exists, whereby, pursuant to the procedural obligations under Article 2, a death occurs outside the territory of a state. As per the H.F. and others v. France case, ¹¹ ‘special features’ may be capable of giving rise to extraterritorial jurisdiction where a contracting state had control over the area in question, a jurisdictional link could be established and where there were ‘connecting ties’ to the territory in question. ¹²

In applying these rules in Duarte, the Court stated that the ‘applicants’ complaints in the present case did not correspond to any of the circumstances which in earlier cases have given rise to a finding of extraterritorial jurisdiction.’ ¹³ The jurisprudence of the Court therefore provided no basis for establishing extraterritorial jurisdiction of the respondent States (other than Portugal, which had territorial jurisdiction). ¹⁴ The Court sought to determine whether there were grounds to expand the existing case law on extraterritorial jurisdiction. The Convention is interpreted as a living instrument in the broader context of its existence, and the widening of territorial jurisdiction can and does happen, as shown in the exceptions raised above. The Court therefore reviewed the submission of the applicant, which called for the Court to look to other sources of doctrine outside the scope of its jurisprudence. Internationally, other divergent, wider approaches to jurisdiction are not unheard of. In fact, recent case law from the Inter-American Court of Human Rights (IACtHR) as well as the UN Committee on the Rights of the Child (UNCRC) would support this divergence. These bodies adopted what is termed the ‘control over the source doctrine’, which is also aligned with Principle 21 of the Stockholm Declaration, stating that states should not cause environmental harms beyond their borders. ¹⁵ In its recent Advisory Opinion OC-23/17, the IACtHR also decided that jurisdiction within the meaning of Article 1(1) of the Interamerican Convention on Human Rights (ACHR) includes an obligation to prevent environmental harm extraterritorially if the source of that harm lies on their territory. ¹⁶ This view was purported by the UNCRC in its Saachi et al v. Argentina et al judgment (which, however, still rejected the application based on the failure to exhaust domestic remedies). ¹⁷ This approach was explicitly recognized by the Strasbourg Court, which took note of them, but found that these findings were ‘based on a different notion of jurisdiction, which, however, has not been recognized by the Court’s case law’. ¹⁸

C. An expected approach?

At first glance, this difference in approach may seem to be an example of an often-discussed phenomenon in international law: fragmentation. ¹⁹ These approaches are from two high level courts in distinct human rights regimes (and one treaty body, the UNCRC), ruling on very similar issues of extraterritoriality, potentially giving rise to a divergence in approach and of norms. Conversely, it is possible that such a divergence in approach results from jurisdictional specificities between these fora operating according to unique cultural and regional considerations, rather than fragmentation per se. The IACtHR is considered to be at the forefront of developing rights to a healthy environment and is historically considered to be a ‘progressive’ court in this regard. ²⁰ In its consideration of extraterritoriality, the IACtHR considered the merits of the case and the obligations of the IACHR substantively with regard to their extraterritorial application. The Strasbourg Court’s examination of the Duarte case concerned different rules on jurisdiction than the IACtHR and the UNCRC, and thus it is not surprising that the Court found differently than the other bodies. Its rules on jurisdiction and interpretation thereof are of course different, and more narrow.

The overarching aim of this contribution is to identify how international law is engaged with in the April decisions and judgment. Within the scope of the Convention, this decision provides important clarification, in particular that exceptions to the exhaustion of domestic remedies will not apply to climate-related cases and that the Court will not expand its stance on extraterritoriality because of the inherently cross-border nature of climate change. The Court did not, however, necessarily engage with sources outside of the Convention (as in use them as a lens of analysis or apply them) and therefore the decision does not contribute to the development of common approaches to common questions.

Although the decision will most likely have negligible effects on the development of climate change law outside the context of the ECHR, it did provide important clarification on the admissibility of future applications before the Court. It is now clear that although climate change is a unique threat to human rights, applicants still have to satisfy the Court’s tests on territoriality and victim status.

3. KlimaSeniorinnen

A. The dispute at hand and the reasoning of the Court

The KlimaSeniorinnen case is, by far, the most far-reaching of the three rulings delivered in April 2024, and potentially the most influential on the development of multi-level understandings and interpretations of international climate change law. The application was brought by four individuals (members of the association Verein KlimaSeniorinnen Schweiz), and the association itself. The applicants alleged that the Swiss government’s climate action plans and the actions and policies undertaken by the Swiss government were insufficient to mitigate climate change. They submitted that this failure to mitigate effects would entail a violation of Article 2 ECHR and therefore a failure to adequately protect the right to life, and a failure to ensure respect for their private and family life, including their home within the meaning of Article 8 ECHR. The applicants further alleged a violation of Article 6(1) ECHR, stating they had not had adequate access to a domestic court. Lastly, the applicants complained of a violation of the right to an effective remedy under Article 13 ECHR, arguing that no effective domestic remedy had been available to them for the purpose of submitting their complaints under Articles 2 and 8 ECHR.

The Court affirmed in concrete terms that climate change falls within the remit of the Court’s rationae materiae jurisdiction, given that this phenomenon has far-reaching consequences for human rights. The Court went into detail laying out the national and international legal frameworks concerning climate change, as well as domestic climate change litigation. ²¹ The Court stated that it is a well-established fact that anthropogenic climate change exists, and that human rights worldwide are affected, ²² and recognized the complexity of the issue. Within the meaning of Article 19 ECHR, the Court found that it does have the competence to engage with issues of climate change.

The Court then reviewed the individual applicants’ victim status and the association’s locus standi, as well as the application of Articles 2 and 8 ECHR. The Court distinguished between environmental cases, where the harm is usually localized and personal, to those of climate change, where harm is general and not traceable to one specific (in)action, thereby establishing a new test for victim status of individuals. ²³ It noted that for climate change cases such as the one at hand, the question is how and to what extent ‘allegations of harm linked to state actions and/or omissions in the context of climate change, affecting individuals Convention rights,…can be examined without undermining the exclusion of actio popularis…and without ignoring the nature of the Courts judicial function which is by definition reactive rather than proactive’. ²⁴ This distinction between environmental and climate change law cases is a rational one. Climate change affects, by its nature, every human, albeit to varying degrees, and the Court had to balance the need to protect the rights of individuals and the need to make sure that an actio popularis, or general public interest litigation action, was not created. A specific harm must therefore be identified, whereby an applicant can show that they were indeed affected, personally and directly, by the failure of the State to regulate appropriately. Therefore, for Article 34 ECHR to be satisfied, two criteria need to be met: (1) ‘a high intensity of exposure to the adverse effects of climate change’ and (2) a pressing need to ensure the applicant’s individual protection, owing to an absence of measures to reduce harm. ²⁵ This victim status for individuals is a rather high bar, especially when juxtaposed against the locus standi requirements for associations, and the primary motivation for this is to avoid actio popularis, which is not provided for by the ECHR.

In examining the standing of the association, the Court recognized the important place of Environmental NGOs (ENGOs) in society, especially with regard to the protection of the environment. ²⁶ For these groups to be able to bring an application before the Court, they must show that they are (1) lawfully established in the jurisdiction concerned or have standing to act there, (2) able to demonstrate that the organization pursues a dedicated purpose, clear through its statutory objectives, in the defence of human rights of its members, whether limited to or including collective action for the rights against the threats of climate change and (3) able to demonstrate that they actually represent their members. The Court found that the association, not the individual members, had standing, and that Article 8 ECHR was applicable in the case.

On its examination of the merits, the Court stated that it would not review the case in the context of Article 2 ECHR, reaffirming that ‘to a great extent the Court has applied the same principles as those set out in respect of Article 2 when examining cases involving environmental issues under Article 8’ ECHR. ²⁷ Furthermore, the Court restated that as the individual applicants lacked standing, it is unnecessary to review their claims with regard to Article 2 ECHR. The Court then clarified the protection provided by Article 8 ECHR to include the protection against the adverse effects of anthropogenic climate change. ²⁸ The Court found that states (in general, not specific to Switzerland) have a duty to adopt and practically apply regulations and measures capable of mitigating the effects of climate change. While the Court was clear that it only had the competence to review the obligations stemming from the Convention and its Protocols, it did so in light of State Parties’ existing obligations under the climate change law regime (the UNFCCC and the Paris Agreement specifically), as well as the scientific evidence of the IPCC. ²⁹ The exact policies and regulations are to be left to the State themselves, as long as they are informed by the scientific evidence of the IPCC and the guidance of the climate change regime. Article 8 ECHR further requires that ‘each Contracting State undertake measures for the substantial and progressive reduction of their respective greenhouse gas (GHG) emission levels, with a view to reaching net neutrality within, in principle, the next three decades’. ³⁰ This was the first aspect of the test introduced by the Court: states must introduce regulation, in light of science and international law, and with the goal of achieving net neutrality. The second, stricter, branch of this test was with regard to the substantive nature of the measures adopted.

The Court introduced five factors which will be reviewed when assessing whether a state has remained within its margin of appreciation, namely when they have due regard for the need to:

adopt measures which specify a target timeline for achieving carbon neutrality and a carbon budget,

set out emission reduction targets in the intermediate term which meet the overall reduction goals,

provide evidence to support the assertion that these authorities have complied with emission reduction targets specified,

update these emission reduction targets with due diligence based on the best available science,

act in a timely, appropriate and consistent manner when implementing the legislation in question. ³¹

The Court specified that these requirements must not all be completely satisfied, but that the ‘Court’s assessment of whether the above requirements have been met will, in principle, be of an overall nature’, ³² meaning that if perhaps one of the criteria is not met, it does not necessarily mean that a state is not satisfying its obligations to effectively regulate.

The Court therefore introduced a dual margin of appreciation, one whereby states are firstly required to, broadly speaking, legislate and regulate to prevent the adverse effects of climate change. Then this margin has a further step, requiring these obligations to meet the above mentioned five criteria. This will have far-reaching consequences for the internal Convention system, in that the Court introduced a concrete test for states climate obligations under the Convention, and introduces a means to challenge government (in)action under the umbrella of the protection afforded by Article 8 ECHR.

In reviewing the specific case of Switzerland, where there was a vacuum of effective climate policy and little means of recourse for concerned associations, the Court found that there had been a violation of Article 8 and Article 6 ECHR.

B. Engagement with the Paris Agreement

At various points in the Court’s analysis, it situates the respondent’s obligations under the Convention in the broader context of the obligations stemming from the international climate change regime. The primary sources of these obligations are the 1992 United Nations Framework Convention on Climate Change (UNFCCC) and the 2015 Paris Agreement.

Adopted on 12 December 2015, the Paris Agreement has as its central goal to strengthen the global response to climate change, and to hold the average increase in global temperature to well below 2 degrees Celsius above pre-industrial levels and to pursue efforts to limit the increase to 1.5 degrees Celsius. ³³ This is, however, a goal which is ‘framed in aspirational language, and as such does not impose binding obligations on state parties’. ³⁴ The legal character of specific provisions of the Paris Agreement is a question which has been the topic of many scholarly studies, and is also reflected in the drafting history. ³⁵ Some provisions are in the imperative, with language such as ‘shall’ and ‘will’, with others using more ambiguous language, such as ‘should’, which leave the exact obligation to be derived from them rather unclear. The goal of the Agreement is operationalized through an intricate system of NDCs laid out in Article 4 of the Agreement.

In KlimaSeniorinnen, the Court engaged with the Paris Agreement and its obligations, and used them as a lens for interpretation when reviewing the obligations of states under the Convention. This is evident in the Court’s interpretation of Article 8 ECHR. The Court read the Convention and Switzerland’s obligations under it, ‘in line with the international commitments undertaken by the states (…)’, ³⁶ and therefore in light of the Paris Agreement and the international climate change regime, relying on its interpretative approach of the Convention as a ‘living instrument’. ³⁷ This doctrine is a ‘method of judicial interpretation (…) whereby the ECHR is interpreted in light of “present day conditions”’ and these conditions in the case at hand, include the specialized regime of the UNFCCC and the Paris Agreement. ³⁸ The Court adopted a standard of conduct whereby states have to ensure appropriate ambition of climate action in light of their human rights obligations and the Paris Agreement’s goals. This interpretive approach strengthens the Paris Agreement, at least for those countries which are State Party to both the ECHR and the Paris Agreement itself. This, however, was not the only ‘use’ for the Paris Agreement in the KlimaSeniorinnen case, as the Court also engaged heavily with the temperature target.

A fundamental goal of the international climate change law regime is to limit the global average temperature increase to well below 2 degrees Celsius, and to pursue efforts at limiting it to 1.5 degrees. This goal, which is mentioned and relied upon in the KlimaSeniorinnen merits, has historically been subject to (significant) development, primarily through decisions of the Conference of the Parties to the UNFCCC and the Paris Agreement. Article 4 describes Article 2 as the ‘goal’ of the Agreement. ³⁹ Although it does not itself create any actual actionable obligations for individual parties, the provision is highly relevant and contains strong normative language. ⁴⁰ This goal is operationalized through Article 4(1) of the Agreement which envisages a global peaking of gas emissions as soon as possible, followed by rapid reductions, to achieve a ‘balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases in the second half of the century’. ⁴¹ As such, this article foresees a short term peaking of emissions, followed by a rapid medium-term reduction, and a net-zero situation in the long term. As Rajamani has noted, Article 2 states ‘where we need to be, while the “aim” described in article 4(1) of the Agreement describes what, collectively, we need to do to get there’. ⁴²

It does not, however, provide a concrete pathway of action for parties, and lacks precision. ⁴³ For example, where Article 2 lays out two temperature goals, Article 4(1) of the Agreement only refers to ‘the temperature goal’. Furthermore, although the provision ‘indicates a direction of travel’ ⁴⁴ it does not lay out a specific time frame, or a methodology for achieving the end goal. This is, as such, an element which is left to the State Parties, in line with the Agreement’s general strategy of leaving specific mitigation policies under the purview of the parties.

Article 2 of the Agreement has been subject to significant development. Until 2021, there was little legal or political focus on the 1.5-degree temperature ceiling set out in Article 2. Then, in 2021 at the 26th CMA in Glasgow, a renewed focus on the 1.5-degree goal was achieved. Following the conclusion of the Paris Agreement, many countries considered that a level of warming close to 2 degrees Celsius would ‘not be safe and that there was only limited knowledge about the implications of a level of 1.5’ degrees Celsius, and therefore invited the IPCC to assess the impacts of such warning, which resulted in The Special Report on the Impacts of Global Warming of 1.5 Degrees Celsius above Pre-industrial Levels and Related Global Greenhouse Gas Emission Pathways, in the Context of Strengthening the Global Response to the Threat of Climate Change. ⁴⁵ Following this, the international community (in the form of the CMA) refocused efforts. Essentially, the ‘question of which one of the two temperature goals exerts a stronger normative power has been “concretized”’ by this decision. ⁴⁶ This was further reaffirmed in the outcome at the CMA in Sharm El-Sheikh in 2022, where the 1.5 degree trajectory was again underlined. ⁴⁷

Many of the Paris Agreement’s obligations are designed to be implemented at the national level and to become more ambitious over time. This requires a system of dynamic decision-making, whereby obligations can be concretized, and their implementation overseen constantly by the CMA through its decisions. This brings to light an important tangential question, namely what exactly is the legal character of a decision from such a treaty body? There is no clear legal answer in the current public international law theory and scholarship, and the mechanism is shrouded in ambiguity. Writing before the adoption of the Agreement, Bodansky questioned whether a COP decision would fit into the definition of the Durban Mandate, to create a new agreement with force under the UNFCCC. He instead found that a decision of a Conference of the Parties is never binding, unless the constitutive treaty, or mother treaty, deems them to be. ⁴⁸ Brunnée also argued that such decisions are de jure non-binding, but may be de facto binding, as they can contain mandatory conduct requirements but are not binding unless the treaty says. ⁴⁹ Voigt argues that ‘although a decision by the CMA cannot replace or overwrite provisions of the Paris Agreement, it can be argued that the subsequent agreement as expressed in the consensus based CMA decisions has normative bearing on the temperature goals of the Agreement.’ ⁵⁰

C. The Court’s approach to external norms

In the KlimaSeniorinnen judgment, the Court discusses the international climate law regime’s temperature goal multiple times. It does so, not in framing it as an ambition, but rather as a binding requirement incumbent upon State Parties. ⁵¹ In its assessment, the Court lays out the relevant ‘facts in relation to climate change emerging from material available to the Court’, and extensively reviews the IPCC’s Assessment and Synthesis reports in relation to the 1.5-degree Celsius goal and its pathways. It recognizes the initial goal of the Paris Agreement mentioned above, but states that ‘(s)ince then, scientific knowledge has developed further and states have recognized that “the impacts of climate change will be much lower at the temperature increase of 1.5-degree Celsius compared with 2-degree Celsius” and thus resolved “to pursue further efforts to limit the temperature increase to 1.5-degree Celsius” (see Glasgow Climate Pact, paragraph 21, and Sharm el-Sheikh Implementation Plan, paragraph 4).’ The Court therefore recognizes that, due to new scientific evidence, the international community, in the form of the CMA, shifted the normative attention from 2 degrees Celsius to 1.5 degrees Celsius.

The question arises whether this approach is indeed the correct one, and whether the reasoning of the Court is convincing. The Court implicitly recognizes the importance of the CMA decisions and gives them a significant legal position in its analysis, recognizing them, in a way, as legal fact, or at least an expression of the will of the parties to the Paris Agreement. It does so without explicitly analysing the legal nature of these decisions as such. This is as such not surprising, for a number of reasons. Firstly, the design of the Paris Agreement and the climate change regime itself place much responsibility in the hands of the treaty body. It is responsible for deciding timelines, providing detailed rules on implementation, and discussing further cooperation and legal action in the context of the Regime.

The second reason is that these decisions are adopted at the CMA through consensus, meaning that there must be unanimous agreement, or at least no disagreement, with the content of the decision. This means that these decisions, which are heavily negotiated upon before adoption, do represent, in theory, the political consensus of all parties to the Agreement. ⁵² Voigt refers to this as a ‘subsequent agreement’ within the meaning of Article 31(2)(a) of the Vienna Convention on the Law of Treaties, and therefore a key interpretative tool when assaying the meaning of the Agreement in question. ⁵³

The third reason is that the legal character of CMA decisions and the consideration thereof in literature is changing. As mentioned previously, before the Paris Agreement had been concluded, there was a major gap in the literature examining such treaty bodies. When literature did exist, it mostly concluded that the legal bindingness of such a decision would depend on the governing treaty itself. Voigt notes that because of the design of the body, as well as its voting procedure, and history of decisions, CMA decisions are increasingly being seen as having much value in terms of the development of norms. ⁵⁴ If the Court had turned a blind eye to the decision of the CMA, and instead employed a strict textual reading of the Paris Agreement, it would be ignoring years of scientific (with the reports of the IPCC) and political consensus.

A final reason which is important to note, is that the 1.5-degree Celsius goal was not debated by the respondent state. This lack of objection to the nature of the goal is potentially not representative of other State Parties’ considerations of said goal, it does represent further solidification of the political, scientific and legal shift to 1.5 degrees Celsius as a required maximum temperature increase. The importance the Court’s consideration of the temperature target is in its implicit recognition of the norm-creating, or at least developing, possibility of the CMA decisions. This reasoning not only further concretizes the political and legal shift towards capping temperature increase at 1.5 degrees Celsius, but also the legal relevance of CMA decisions. This shows that these decisions take up a uniquely important role in the international climate change law regime, allowing for the development of norms outside the traditional law-making mechanisms of international law.

A recurring question which arises when reviewing the Court’s engagement with the climate regime is whether the Court’s analysis strays from the approach previously adopted when interpreting external sources of international law. While the present analysis is essentially devoted to the effect of the Court’s engagement with the Paris Agreement, it is also important to question whether the Court is straying from its usual approach to other sources of international law, outside the ECHR. The Court is consistent in its view that the Convention is part of international law. It follows that ‘the Convention…cannot be interpreted in a vacuum. …should so far as possible be interpreted in harmony with other rules of international law of which it forms part of.’ ⁵⁵ Furthermore, the Convention should be interpreted in light of the Vienna Convention on the Law of Treaties, and has held that ‘account is to be taken of any relevant rules of international law appliable in the relations between parties’. ⁵⁶

The Court does not have one consistent, clear approach to analysing sources of international law outside of the ECHR space. Each topic the Court engages with is ‘subject to its own treatment’. ⁵⁷ According to Koskenniemi, the main approach to regulating the interaction between sub-disciplines of international law, is that of lex specialis. ⁵⁸ This allows the Court to interpret general international law through the lens of human rights, but also should encourage the Court to draw from more specialized regimes when ruling on matters of, inter alia, climate change. Furthermore, the Court interprets the Convention in its legal and factual context, according to the dynamic interpretation of the Convention as a ‘living instrument’. ⁵⁹ This goes to show that the Court taking the international climate change law into account when ruling upon issues of human rights and the climate is not surprising, as this regime exists specifically to regulate the relations between states in regard to the climate. It is fundamental, therefore, that these pre-existing inter-state relations be taken into account. It appears in the KlimaSeniorinnen case, the Court took a similar approach to its usual practice as in other areas of law, and it considered the context of the provisions in questions as well as the political and factual realities of the case in question.

D. The Court’s assessment of the role of courts in climate change

The KlimaSeniorinnen case raises a recurring theme in climate litigation, namely the role of domestic courts in the context of the obligations states have with regard to climate change. In domestic litigation, respondents, whether private entities or actors in the executive branch, often claim that the setting of NDCs or targets should not subject to review by courts, as they are executive, political actions. ⁶⁰ This question was referred to in the recent Klimaatzaak case for example, ⁶¹ which concerned an alleged violation of Articles 2 and 8 ECHR by the Belgian Federal State, regions and the city of Brussels. There, the respondent regions and the Belgian federal government asserted that the question of a State’s approach to emissions reductions is so complex, involving a wide array of economic, social and political questions, that they must be decided by the executive and legislative powers, especially since overly ambitious policy could result in energy poverty. ⁶² The Belgian Court of Appeal held that a violation of the ECHR rights in question could be found by the judiciary, so long as it is shown that the public authorities failed to take appropriate and reasonable measures, in light of the best scientific knowledge at the time (and therefore without any discretionary powers) to enable them to prevent to the best of their ability the crossing of a dangerous threshold to life and likely to seriously undermine respect for private and family life. ⁶³

In Germany, with the Neubauer case, the Bundesverfassungsgericht (German Federal Constitutional Court) also rejected the argument that the compliance with international climate change obligations is not reviewable by domestic courts, finding instead that the Basic Law, specifically Article 20a, obliges the legislature to protect the climate and aiming towards climate neutrality. They found that ‘the fundamental rights – as intertemporal guarantees of freedom – afford protection against the greenhouse gas reduction burdens imposed by Art. 20a of the Basic Law being unilaterally offloaded onto the future’, and that domestic courts are key to protecting these rights. ⁶⁴

In a judgment handed down shortly before the ECtHR decisions, an Italian tribunal in the Giudizio Universale case dismissed a claim based on a lack of jurisdiction due to the separation of powers. ⁶⁵ The Tribunal held that ‘the decisions pertaining to the ways and timing in which anthropogenic climate change is to be handled…fall within the competence of the political organs and cannot be ruled upon in the present case’, thus rejecting the logic of the aforementioned cases, and clearly rejecting any notion of court involvement in climate litigation. ⁶⁶

In the Thomson case from New Zealand, the New Zealand High Court (NZHC) assessed the question of justiciability quite extensively. ⁶⁷ The claimant alleged that the 2030 NDC target was made with ‘a failure to take into account relevant considerations.’ ⁶⁸ The respondents alleged that this was a governmental decision, claiming it was not amenable to review since it was set in accordance with an international obligation not incorporated into national law. ⁶⁹ Further, the defendant claimed that these are ‘socio-economic and financial policy, requiring the balancing of many factors’ ⁷⁰ and not susceptible to a determination made by ‘legal yardstick’. ⁷¹ The NZHC held, however, that it is not determinative if the international obligation is incorporated into domestic national legislation. ⁷² The NZHC referred to several domestic judicial decisions from other jurisdictions, ⁷³ to infer that courts have been more open to review climate change related decisions of governments and the executive. After an extensive evaluation of the case law of other systems, the NZHC found that:

The Courts have not considered the entire subject matter is a ‘no go’ area, whether because the State had entered into international obligations, or because the problem is a global one and one country’s efforts alone cannot prevent harm to that country’s people and their environment, or because the Government’s response involves the weighing of social, economic and political factors, or because of the complexity of the science. The Courts have recognised the significance of the issue for the planet and its inhabitants and that those within the court’s jurisdiction are necessarily amongst all who are affected by inadequate efforts to respond to climate change. ⁷⁴

Further, in the Thabametsi case in South Africa, the respondent, the South African Department of Environmental Affairs, argued that the assessment of climate change as an impact could not be considered a mandatory requirement for such an administrative decision. ⁷⁵ The respondents contended that the government made such decisions not the courts, and did so all the while balancing South Africa’s developmental needs and climate change impacts. ⁷⁶ They also argued that, failing this, the permit is consistent with South Africa’s NDC, which envisages a peak in emissions in 2020. ⁷⁷

In the KlimaSeniorinnen case, the group of senior women instituted their case as early as 2016, claiming that various bodies of the Swiss Government had failed to uphold obligations under the ECHR, due to a lack of ambitious climate plans. The applicants submitted a petition to the Government and various specialized agencies, asking them to develop an appropriate framework and regulatory approach. This petition was rejected in 2017, and then again by the Swiss Federal Administrative Court in November 2018, where the Court said that the women were not affected by climate change impacts in a specialized way, and therefore lacked interest. This was appealed by the applicants and eventually rejected by the Supreme Court in May 2020. Having exhausted all domestic remedies available to them, the applicants submitted a complaint to the ECtHR. ⁷⁸

The ECtHR confirmed that domestic courts, through judicial review, do have a role to play in addressing anthropogenic climate change. The Court began its assessment by recognizing that in order to prevent the adverse effects of climate change, legislative action ‘both in terms of the policy framework and in various fields’ is required, and such action ‘depends on democratic decision making’. ⁷⁹ Furthermore, judicial intervention ‘cannot replace or provide any substitute for the action which must be taken by the legislative and executive branches of the government.’ ⁸⁰ However, such democracy ‘cannot be reduced to the will of the majority…in disregard of the requirements of the rule of law’ and the role of domestic courts is therefore complementary to these democratic processes, providing essential judicial oversight. Furthermore, the Court emphasized the ‘key role which domestic courts have played and will play in climate change litigation, (…) highlighting the importance of access to justice in this field’. ⁸¹ The Court found a violation of the Convention rights aforementioned, but the judgment as such was declaratory, leaving the measures to be taken to the Swiss authorities themselves.

There are considerable differences in the approaches of national systems when considering the question of the role of Courts in climate change governance. ⁸² In Klimaatzaak the Belgian Court of Appeal highlighted the need for a new target, and public authorities (the Federal State, Flemish Region and the Brussels-Capital Region) were ordered to reduce their GHG emissions of 55% compared to the 1990 level by 2030, based on the breach Articles 2 and 8 ECHR. ⁸³ In the Urgenda case, the High Court in the Hague imposed a target on the legislature. In Neubauer, the German Constitutional Court did not strike down the target itself for a lack of ambition, but instead reviewed the pathway the Government outlined to achieve this target, and found that this pathway was not elaborated enough, thus ordering the legislature to revise the strategy. Regardless of the approach of the domestic courts in their respective contexts, what has been made clear through the judgment of the ECtHR is that, at least in the Convention system, domestic courts do have an important role to play in safeguarding human rights affected by climate change.

An important development with regard to the KlimaSeniorinnen case is that at the time of writing, the Swiss parliament’s lower house voted to disregard the judgment, a declaration not binding upon the federal government, but accusing the Court of ‘inadmissible and disproportionate judicial activism’. ⁸⁴ This goes to show that even though the ECtHR and Courts generally see climate change as well within the realm of their jurisdictions, political reality is also of course important. How the federal government responds to the position of the Lower Chamber could signal the perceptions of political legitimacy such cases have and could possibly have broader impacts on the Strasbourg Court’s effectiveness in this regard. What the Strasbourg Court did clearly lay out, is that domestic courts are key actors in the protection of human rights in the context of the climate crises. It clearly ruled that these domestic courts are essential in the governance of climate change and that domestic judicial review serves an important function, to protect human rights in light of international climate change law.

4. Conclusion

In its April decisions, for the first time the Court clarified the content and scope of obligations in the context of climate change. In addition to the introduction of a test for the obligations of states in regard to climate change impacts on Article 8 ECHR, mentioned above, this note argues that from the international climate law perspective there are two notable developments. Firstly, this judgment serves as a further recognition that the climate change regime is dynamic, moving and developing as new scientific knowledge and evidence comes about. This scientific evidence, primarily coming from the Assessment Reports and studies of the IPCC drive the international law making. Furthermore, the recognition that the temperature goal of the Paris Agreement is now below 1.5 degrees Celsius speaks to the normative shift, as well as an inherent recognition that the decisions of the COP/CMA do represent subsequent agreements of State Parties, and therefore also do have legal and normative weight. Furthermore, the Court has further concretized the Paris Agreement’s goals and bottom-up structure, introducing a new positive obligation to adequately combat the effects of climate change in light of the Paris Agreement. The recognition that the science of climate change comes first, in the sense that the margin of appreciation allowed for under Article 8 also lays out that climate change policies must represent the accurate and most recent scientific evidenced, is a positive development.

The second main development identified in this case note is that of the recognition of the role of the judiciary in climate change governance. The Strasbourg Court clearly highlighted that domestic courts are key in the protection of human rights in climate change matters. This represents a significant development, as it is the first time an international human rights court has solidified the role of courts in the debate. There are still many questions to be answered, and the long-term effects of the judgment remains to be seen, but what we do know in this regard is that Strasbourg’s proverbial door is open for applicants to bring their claims there.

Unfortunately, however, as expressed above, the response from the Swiss lower chamber is rather negative, calling for Switzerland to even leave the Council of Europe. This situation reflects an important consideration in climate change litigation; will these cases, where courts go ‘further’ in terms of ambition, result in actual increased ambition and decrease of GHG emissions? Or will these cases lead to anti-judiciary sentiment, with judges and courts being labelled as overly activistic? The only way to answer these questions is unfortunately through more climate change litigation, hopefully spurring more action, rather than leading to a potentially devastating sentiment of scepticisms.

In conclusion, the April decisions have been the subject of much debate and scholarly attention. ⁸⁵ This case note has tracked a number of considerably positive developments, such as the recognition of the important law-developing function of the COP/CMA, or the recognition of the role human rights have to play in combatting climate change, while also underlining a potential negative impact, the sceptical response of the Swiss Chamber to the Council of Europe and the Court. Only time will be able to shed light on the role these cases will have in the global, all-encompassing problem of combatting climate change, but the Court has now issued in-depth guidance on the review standard of climate policies necessary to satisfy the obligations of Article 8 ECHR for domestic authorities.