1 - Litigating the Climate Emergency

Summary

This chapter presents the results of a comprehensive study of the universe of rights-based climate cases filed in domestic courts and in regional and international judicial and quasi-judicial bodies between 2015 and 2021. Part I offers an overview of human rights-based climate change (HRCC) litigation. Part II analyzes the legal rules and principles emerging from HRCC lawsuits and court decisions around the world. Part III offers conclusions about the potential and limitations of HRCC litigation in advancing climate action.The chapter argues that the regulatory logic and the strategy of HRCC litigation should be examined at the intersection of international and domestic governance. Litigants have predominantly followed a two-pronged strategy. They have (1) asked courts to take the goals of the climate regime (as set out in the Paris Agreement and IPCC reports) as benchmarks to assess governments’ policies and (2) invoked the norms and enforcement mechanisms of human rights to hold governments accountable for such goals. In the face of governments’ reluctance in taking the urgent measures that are needed to address the climate emergency, HRCC litigation can be fruitfully viewed as a bottom-up mechanism that provides domestic traction for the international legal and scientific consensus on climate action.

In April 2021, the German Constitutional Court stunned observers and even the young plaintiffs who had challenged the country’s climate law by holding that “the national climate targets and the annual emission amounts allowed [by the Federal Climate Change Act] until 2030 are incompatible with fundamental rights insofar as they lack sufficient specifications for further emission reductions from 2031 onwards.”¹ The court’s landmark judgment in the Neubauer case prompted the government to increase its 2030 greenhouse gas (GHG) emissions reduction target, specify further increases thereafter, and move up the date of net carbon neutrality to 2045. The ruling built on and expanded legal innovations introduced by litigants and courts since the mid-2010s on issues such as the impact of global warming on human rights, judicial review of governmental action on climate change, the rights of future generations, and the binding nature of governments’ international pledges on climate action.

Among the key precedents quoted by the German Constitutional Court is the 2019 Dutch Supreme Court’s ruling in the Urgenda case, which upheld the lower courts’ rulings from 2015 to 2018 that the Dutch government has a duty to urgently and significantly slash the country’s planet-warming emissions.² Urgenda was the first case to establish that climate inaction is a violation of internationally recognized human rights and to hold a government legally accountable for its international commitments and national targets regarding GHG emission cuts. The court ordered the government to increase the nation’s GHG emissions reduction target from 20 to 25 percent relative to 1990 levels by the end of 2020 – in line with the country’s prior target and the minimum contribution required from industrialized countries for the planet to avoid the most extreme scenarios of global warming, according to the scientific assessments of the UN Intergovernmental Panel on Climate Change (IPCC) and the goals of the 2015 Paris Agreement, both of which the Dutch Supreme Court cited extensively in its ruling, just as the German Constitutional Court would do in Neubauer.

Prior to 2015, only nineteen rights-based climate cases had been filed anywhere in the world, according to the database compiled for this study. Launched in early 2020 and updated regularly, this is the first specialized database to collect detailed information about human rights and climate change (HRCC) cases, based on a systematic reading of submissions and rulings as well as interviews with key actors in cases filed before national and international judicial and quasi-judicial bodies (see Table 1.1 in the Appendix for the list of cases).³ Between 2015 and December 2021, litigants brought 148 climate cases involving rights language or arguments in thirty-eight national jurisdictions and in eleven international judicial or quasi-judicial bodies. As Figure 1.1 shows, human rights–based climate cases proliferated at a steady pace in this period, even as (and sometimes as a reaction to) progress stalled with regard to the implementation of the 2015 Paris Agreement.

Figure 1.1 HRCC cases filed per year

Outside of the United States, the proportion of climate cases that are argued on human rights grounds has risen to approximately 91 percent since 2015, with Europe as the most active region with respect to rights-based climate litigation (see Figure 1.2).⁴ Urgenda-like suits have been filed, with mixed results, in, for example, Belgium, Brazil, Canada, the European Union, France, Germany, India, Ireland, Nepal, South Korea, Spain, Switzerland, and the United Kingdom.⁵ Beyond Europe, in 2015, Pakistan’s Lahore High Court found that the government’s delay in enacting the country’s climate laws violated citizens’ fundamental rights.⁶ In 2018, the Colombian Supreme Court ruled in favor of young plaintiffs who sued the government to hold it accountable to its own international climate-related pledge to reduce deforestation in the Amazon region.⁷ Other rights-based lawsuits involving young plaintiffs have been filed in Argentina, Australia, Brazil, Canada, the European Union, Germany, India, Mexico, Pakistan, Peru, South Korea, the United Kingdom, and the United States, as well as in the European Court of Human Rights.⁸ Courts and human rights bodies in the Global South – from South Africa and Indonesia to the Philippines and India⁹ – have formally recognized climate harms as human rights violations. In 2022, the Brazilian Supreme Court held that the Paris Agreement should be enforced as a human rights agreement, and held the government accountable for the human rights violations stemming from omissions driving deforestation in the Amazon.¹⁰

Figure 1.2 HRCC cases per region since 2015

At the international level, in a case against New Zealand, the United Nations Human Rights Committee held that states have a duty to refrain from sending asylum seekers back to another state in which their life or physical integrity would be seriously endangered due to climate harms.¹¹ A petition filed by Greta Thunberg and other young climate activists against Argentina, Brazil, France, Germany, and Turkey asked the UN Committee on the Rights of the Child to declare that the respondents have violated the petitioners’ rights by contributing to global warming and to recommend actions for respondents to reduce GHG emissions and adapt to the impacts of climate change.¹² And though the Committee ultimately dismissed the petition on procedural grounds, they did find that states can be accountable for harms resulting from emissions generated within their territory and felt by children living outside their territorial borders.

Commenting on a handful of early lawsuits in this trend, analysts rightly identified a “rights turn” in climate litigation.¹³ Thus far, the literature on this trend has tended to focus on accounts of one case or a few particularly successful cases.¹⁴ In the absence of systematic analyses of the “rights turn,” we lack a robust understanding of its legal doctrines and implications for climate action.

This edited volume helps fill this scholarly and practical gap. This chapter provides the empirical background for the subsequent chapters and proposes a framework for understanding the key traits and emerging norms of rights-based climate litigation. In it, I summarize the results of my study of the universe of HRCC cases filed in domestic courts and in regional and international judicial and quasi-judicial bodies. Drawing on theories of global governance and legal mobilization, I elsewhere have offered an extended discussion of the results of the study.¹⁵ In doing so, I have sought to theorize and empirically document the origins, typology, norms, and impact of the rights turn, as well as its interaction with the adoption and implementation of the 2015 Paris Agreement.

This chapter focuses on the post-Paris period, during which the large majority of cases have been filed or decided. While I report on the universe of cases, my analysis concentrates on the type of case that predominates both the practice of HRCC litigation and the chapters in this book – that is, lawsuits that primarily seek to hold states accountable for their duties regarding climate mitigation (i.e., the reduction of planet-warming emissions) as opposed to their duties regarding climate adaptation (i.e., the protection of people and ecosystems from the already inevitable impacts of global warming). This analytical choice is justified by the fact that approximately 94 percent of HRCC cases filed since 2015 are primarily geared toward expanding and speeding up climate mitigation. The focus on state targets (rather than corporations) is explained by the fact that approximately 85 percent of HRCC cases filed since 2015 target governments.

I argue that the regulatory logic and the strategy of HRCC litigation should be examined at the intersection of international and domestic governance. Specifically, I posit that litigants have predominantly followed a two-pronged strategy. They have (1) asked courts to take the goals of the climate regime (as set out in the Paris Agreement, IPCC reports, and other authoritative sources) as benchmarks to assess governments’ climate action and (2) invoked the norms, frames, and enforcement mechanisms of human rights to hold governments legally accountable for such goals. In the face of governments’ reluctance or hostility toward taking the urgent measures that are needed to address the climate emergency, HRCC litigation can be fruitfully viewed as a bottom-up mechanism that provides domestic traction for the international legal and scientific consensus on climate action. Put differently, HRCC litigation contributes to addressing the climate emergency by providing at least part of the missing link between international promises and domestic action. In so doing, it offers a much-needed leverage point for scaling and speeding up climate action at a moment when time is running out to prevent the most catastrophic scenarios of global warming.

However, climate change is too complex a problem for any single regulatory tool to adequately address. Rights-based litigation is only one such tool – one that, as we will see, has its own challenges and blind spots, including insufficient attention to climate adaptation and the limitations of human rights norms in dealing with the complex causality and temporality of global warming.

This chapter proceeds in three sections. In Section 1.1, I offer an overview of trends in HRCC litigation after the Paris Agreement and characterize the dominant type of case in this period. In Section 1.2, I analyze the legal rules and principles emerging from HRCC lawsuits and court decisions. Rather than examining the outcomes and impacts of these cases (which I have done elsewhere),¹⁶ here I am primarily concerned with norm emergence – that is, identifying new norms that HRCC adjudicators and litigants, regardless of outcome, are articulating to address the unique regulatory challenges of climate change. In Section 1.3, I offer some conclusions about the potential and challenges of HRCC litigation in advancing climate action.

1.1 The Post-Paris Regime and Climate Rights Litigation

The Paris Agreement’s regulatory logic stands in contrast with the pre-Paris regime. In terms of de Búrca, Keohane, and Sabel’s typology of global governance, international climate governance went from an unsuccessful effort to establish an integrated, top-down regime (the 1997 Kyoto Protocol to the UN Framework Convention on Climate Change) to an ongoing attempt to consolidate a bottom-up, experimental regime (the Paris Agreement) that creates incentives for states to act on climate change through an iterative process of international negotiations, domestic civil society pressure, emissions reporting based on IPCC methodologies, and periodic stocktaking and peer review of progress on climate mitigation and adaptation.¹⁷

The Paris Agreement does not establish a binding obligation for states to implement their nationally determined contributions (NDCs) to emission cuts, nor does it specify any procedure to ensure that states are transparent in their accounting of those contributions.¹⁸ Since the success of the Paris system hinges on transparency, the model will only work if states have material and reputational incentives to deliver on their commitments and to increase their ambition in order to reduce the considerable gap between the mitigation targets to which they committed in Paris and the emissions cuts that, according to the IPCC, are needed to keep global warming between 1.5°C and 2°C.¹⁹

The large majority of HRCC suits and complaints (which focus on emissions cuts) can be understood as strategies to provide the post-Paris climate regime with procedural and substantive mechanisms for translating the aforementioned targets into legally binding commitments at the domestic level. In the lead-up to and after the 2015 climate summit, litigants have often leveraged the Paris framework to put pressure on states and, to a much lesser extent, corporations.²⁰ As noted, states are the target of all but 22 of the 148 cases filed between 2015 and 2021 (see Table 1.1). The exceptions²¹ are lawsuits filed against oil companies Shell in the Netherlands (one case) and in South Africa (one case), Total in France (two cases), PetroOriental SA in Ecuador (one case), and Wintershall Dea in Germany (one case); a case filed against Casino in France; a case filed against Electricité de France; two cases filed against automobile companies in Germany; a case challenging corporations with high GHG emissions in New Zealand; a case challenging a proposed coal mine in Australia; OECD complaints filed against the Polish company Group PZA S.A. and a company involved in fracking in Slovenia; a case filed against a private pension company in the United Kingdom; five cases challenging thermoelectric power plants in Argentina; and one case challenging a coal-fired power plant in Japan, as well as the multiyear, transnational inquiry launched by the Philippines Commission on Human Rights against the forty-seven largest fossil fuel companies known as “carbon majors.”²² The commission initiated the inquiry in response to a complaint filed on international human rights grounds by Greenpeace and Filipino citizens affected by Typhoon Haiyan and other extreme weather events, whose occurrence has been made more likely by global warming. In May 2022, the commission released its final report, which incorporated a number of legally significant findings, including, among others, that “the corporate responsibility to refrain from contributing to climate change impacts that impair the full enjoyment of human rights extends not only to the whole group of companies of each Carbon Major … but also to all business enterprises in each of the Carbon Majors respective value chains.”²³ The commission also squarely addressed Carbon Majors’ role in cloaking climate science in doubt and interfering with the transition away from fossil fuels. Namely, in addition to finding that “Carbon Majors, directly by themselves or indirectly through others, singly and/or through concerted action, engaged in willful obfuscation of climate science, which has prejudiced the right of the public to make informed decisions about their products, concealing that their products posed significant harms to the environment and the climate system,” the commission also concluded that this willful obfuscation could serve as a basis for liability.²⁴ At the very least, this made the Carbon Majors, according to the commission, morally culpable.²⁵

In terms of the specific objects of the legal actions, litigants and petitioners have used two general avenues to challenge the actions and inactions contributing to climate change. The first strategy involves challenging state or corporate policies, including – but not limited to – the ambition, speed, or level of implementation of states’ mitigation targets. This is the route followed by approximately 74 percent of the post-2015 cases, including Urgenda and more recent lawsuits such as the one filed in 2021 by Brazilian youth alleging that the glaringly insufficient emissions goal set by the Brazilian government violates its obligations under the National Policy on Climate Change, the Paris Agreement, and the Brazilian constitution. In the Neubauer v. Germany case, the youth plaintiffs challenged not only the insufficient ambition but also the short-term focus and the vagueness of the implementation measures of the German government’s GHG emissions reduction plan. The German Constitutional Court sided with the government with regard to the constitutionality of the overall ambition of the climate plan but declared that the plan’s insufficient detail and urgency violated young peoples’ and future generations’ fundamental rights.²⁶ This also, however, includes a handful of cases that resist policies (or projects) intended to address climate change and aid the transition to zero-carbon economies. In the Matter of the Greenhouse Gas Pollution Pricing Act (Alberta), for example, involved the Alberta provincial government’s attempt to invalidate Canada’s carbon pricing bill, on the grounds that the federal government overstepped its constitutional authority.²⁷

The second route comprises challenges to specific projects and policies that produce GHG emissions on a scale that, according to litigants, is incompatible with states’ duties to act against global warming. For instance, litigants have sued governments to stop new coal or oil projects in Ecuador, Uganda, Tanzania, and Mozambique; new airport strips in Vienna and London; policies promoting deforestation in the Brazilian Amazon; and subsidies to biomass-derived energy projects in South Korea.²⁸ Like with cases targeting policies, this also includes a handful of cases in which plaintiffs challenged projects intended to advance climate action. In IPC Petroleum France v. France, for example, a fossil fuel company challenged the government’s decision to put a time limit on its extraction permit, on the grounds that it, among other things, violated its right to property.²⁹ European Center for Constitutional and Human Rights (ECCHR) and Proyecto de Derechos Económicos, Sociales y Culturales (ProDESC) v. Electricité de France (EDF), moreover, challenges the construction of a large wind farm on the basis that EDF failed to satisfy its obligation to consult with an affected Indigenous community.³⁰

Notably, our database also includes criminal cases brought against climate protesters for their participation in activities challenging either policies or projects that contribute to the climate emergency. While these cases can be categorized according to this policy-project distinction based on the underlying target of the protests, they do operate distinctly insofar as the core of the case does not hinge on a particular policy or project but rather the protests themselves, regardless of their specific intent.

In terms of outcomes, most cases are still pending, which should not be surprising given that the rights turn is a relatively recent phenomenon. As Figure 1.3 shows, approximately 66 percent of HRCC lawsuits are either pending or on appeal.³¹ Moreover, in two cases, the possibility of appeal is still open but not yet taken,³² and in two other cases, there were rulings for the state and there is no evidence that the plaintiffs will appeal.³³

Figure 1.3 Status of cases filed since 2015

The definitive rulings that have been issued by courts thus far are more or less evenly split between outcomes for the plaintiffs and outcomes for the defendants. Indeed, approximately 15 percent have ended with a decision for petitioners, while approximately 14 percent have ended in a definitive ruling for the state. Successful cases include Urgenda Foundation v. Netherlands; Rodríguez Peña v. Colombia (“Amazon’s Future Generations”); Leghari v. Pakistan; in re Carbon Majors; Friends of the Irish Environment v. Ireland; Commune de Grande-Synthe v. France; Notre Affaire à Tous v. France; Castilla Salazar v. Colombia; Save Lamu v. National Environmental Management Authority; Willmeng v. Thorton; Farooq v. Pakistan; Private Corporation for the Development of Asyén v. Environmental Evaluation Service; Instituto Preservar c. Copelmi Mineracaoa Ltda; Moncayo et al. v. PetroAmazonas et al.; Neubauer v. Germany; Shrestha v. Prime Minister; Client Earth v. European Investment Bank; and Development YES – Open Pit Mines NO v. Group PZU S.A., as well as the ruling of the Mexican Supreme Court on ethanol legislation, a successful challenge by Earthlife against South African authorities’ permit for a new coal-fired plant, and a successful challenge against an administrative decision allowing an urban development that would have threatened a local aquifer in South Africa. In Roberts v. Regina, climate protesters who were criminally charged and convicted for public nuisance had their sentences overturned.³⁴ Additionally, an advisory opinion by the Inter-American Court of Human Rights acknowledges an autonomous right to a healthy environment as well as states’ responsibility for territorial or extra-territorial harms to the climate and the environment that violate human rights and can be attributed to their actions or omissions.³⁵ Twenty-three lawsuits since 2015 have ended with definitive rulings for the state or defendant corporation, including: Plan B Earth v. UK Secretary of State for Business, Energy, and Industrial Strategy; Ioane Teitiota v. New Zealand’s Ministry of Business, Innovation and Employment; in re Vienna-Schwechat Airport Expansion; Reynolds v. Florida; Plan B Earth v. UK Secretary of State for Transport (on Heathrow Airport’s third runway); Pandey v. India; the EU Biomass case; Greenpeace Nordic Association v. Ministry of Petroleum and Energy; Armando Ferrão Carvalho v. European Parliament; Friends of the Irish Environment v. Fingal County Council; Zoubek v. Austria; Sacchi v. Argentina; Segovia v. Climate Change Commission; Clean Air Council v. United States; In the Matter of the Greenhouse Gas Pollution Pricing Act (Alberta); In the Matter of the Greenhouse Gas Pollution Pricing Act (Saskatchewan); Greenpeace Netherlands v. Ministry of Finance; Attorney General v. Crosland; Border Deep Sea Angling Association v. Shell; Decision No. 2021-825 DC [“In re Climate Resilience Bill”]; and Views Adopted by the UN Human Rights Committee Concerning the Communication by Ioane Teitiota.³⁶ This also includes “anti-climate action” cases wherein the state prevailed in defending its policy or action intended to address climate change: Portland Pipeline Corporation v. South Portland; IPC Petroleum France v. France; and D.G. Khan Cement Company Ltd. v. Punjab.

Again, given that HRCC litigation is still in its infancy, it is too early to extract hard and fast conclusions about its outcomes. Rather than focusing on outcomes, this and subsequent chapters are concerned with analyzing how litigants and courts have dealt with the complex legal questions posed by climate change through the use of new norms and doctrines emerging from the universe of submissions and rulings, regardless of outcomes. Indeed, this is the task of Section 1.2.

1.2 Key Questions and Emerging Norms in Climate Rights Litigation

Despite the diversity of jurisdictions, litigants, and adjudicators involved in them, HRCC lawsuits tend to revolve around a common set of questions and norms. In sketching emerging legal doctrines and norms, I organize the discussion in terms of the core components of the standard HRCC lawsuit. Rather than an accurate description of the various cases, the model is a Weberian ideal type – a stylized account that is meant to capture the underlying logic that cuts across the large majority of cases. Some lawsuits and decisions approximate the ideal type more than others, but they all exhibit some of its features.

Since procedural rules of standing vary widely across jurisdictions and the large majority of courts that have ruled on HRCC cases have carried out a merits review, I will focus on the substantive norms arising from the typical case, as opposed to procedural rules of standing, in this section. As we will see in Part II, matters of standing – that is, proof of individualized human rights injuries suffered by the plaintiffs and a causal link between those harms and governmental climate action – pose particularly complex challenges for human rights concepts and doctrines, and no clear international norms are currently detectable with regard to these issues.³⁷

The ideal-typical HRCC case proceeds in three steps and spans the two levels (international and domestic) of the post-Paris regime. Each step can be seen as addressing a key legal question:

1. (1) What are the standards that, by virtue of international and domestic law, apply to the judicial assessment of governments’ climate action? The nascent norms and legal doctrines that address this question concern the legal status of international and domestic HRCC standards, from the rules of the Paris Agreement and the IPCC’s recommendations to the rules of international human rights and constitutional rights.

2. (2) In light of those standards, do governments have a justiciable legal obligation to reduce GHG emissions? Courts and litigants tackle this question through emerging norms on the judicial reviewability of climate policy and the existence of a justiciable right to a climate system capable of sustaining human life.

3. (3) Are government policies (regarding emissions targets or specific GHG-emitting activities) compatible with such rights and duties? Emerging norms on this issue seek to set standards, in light of climate change and human rights obligations, governing countries’ “fair share” of contribution to global climate mitigation, the compatibility of governmental actions and policies with this fair share, and the remedies, if any, that courts should grant to hold governments accountable.

In Section 1.2.1, I distill the nascent norms on each of these three issues in turn.

1.2.1 The Baseline Norms: An International “Common Ground” on Climate Rights

The first step in the typical HRCC case is the establishment of baseline rights and duties that apply to the litigation as a matter of climate change and human rights law. In determining the relevant legal standards for judicial assessments of governments’ climate action (or inaction), litigants and courts have often used the European Court of Human Rights’ (ECtHR) doctrine of the legal “common ground” applicable to domestic human rights cases or its equivalent in other regional or domestic regimes.³⁸ In addition to international human rights treaties, this common ground includes other “elements of international law,” states’ interpretations of such elements, and state practice reflecting common values.³⁹ As the ECtHR put it in Demir and Baykara v. Turkey, a judgment widely used by litigants and courts in European climate rights cases: “It is not necessary for the respondent State to have ratified the entire collection of instruments that are applicable in respect of the precise subject matter of the case concerned. It will be sufficient for the Court that the relevant international instruments denote a continuous evolution in the norms and principles applied in international law or in the majority of member States of the Council of Europe and show, in a precise area, that there is common ground in modern society.”⁴⁰

Regardless of the outcome of the case, virtually all of the submissions and rulings on climate mitigation adopt some version of the common ground doctrine.⁴¹ As is evident in Table 1.1, exactly which legal instruments are deemed part of the international common ground varies from jurisdiction to jurisdiction. In general, it comprises universal and regional human rights treaties and declarations ratified by the state – including procedural and substantive environmental rights in international law, which courts and quasi-judicial bodies in the large majority of the cases under examination recognize as a matter of international positive or customary law.⁴²

Importantly, the common ground in HRCC cases includes not only human rights law but also the two central elements of the global climate change regime: the Paris Agreement and the IPCC’s reports. As the IPCC’s findings and recommendations became more explicit and precise with regard to the impact of global warming on human beings in its 2014 and 2018 reports, litigants and adjudicators embraced them as the scientific gold standard for assessing human rights violations. Specifically, they have incorporated the Paris Agreement’s goal of “holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C” into the justiciable international common ground.⁴³ This has been the case regardless of the outcome of the litigation. Courts have used this Paris-IPCC standard in rulings issued against the state for failing to take into account or do enough to contribute to attaining those goals (such as those on Ireland’s climate plan and Mexico’s regulation on ethanol). Courts have also recognized this standard in decisions finding for the state, where they concluded that the government was taking sufficient measures to contribute to achieving those targets – as in Greenpeace Germany v. Germany, in which a group of organic farmers and Greenpeace sought to hold the government accountable to its mitigation goals – or that the plaintiffs did not have standing to sue – as in Verein KlimaSeniorinnen Schweiz v. Fed. Dep’t of Env’t, Transport, Energy & Commc’ns, in which an association of senior citizens demanded greater mitigation ambition by the Swiss government.

If confirmed by future litigation, the emerging recognition of an international normative common ground would consolidate the convergence of human rights, environmental protection, and climate governance. This convergence has been in the making for three decades, through legal developments such as the dissemination of the right to a healthy environment in national constitutions and laws, the proliferation of rights-based environmental litigation around the world on issues such as air pollution, and the articulation of explicit international standards by the UN Rapporteurship on human rights and the environment.⁴⁴

1.2.2 A Justiciable Right to Climate Action

Against this background of common legal and scientific standards, the second step of the post-Paris ideal-typical litigation entails extracting the specific rights and duties regarding climate action that follow from those standards. The key question here is: Do governments have justiciable legal obligations, as a matter of international human rights and climate change law, to reduce GHG emissions?

Regardless of the type and ultimate outcome of the case, judicial and quasi-judicial bodies in HRCC litigation have almost invariably answered this question in the affirmative. Specifically, two emerging norms have been upheld in this body of case law. First, a justiciable right to a climate system capable of sustaining human life has been recognized as following from universally recognized human rights or as included in the constitutional right to a healthy environment. Importantly, some rulings have homed in on the rights of young people and future generations to a livable planet. Recognizing that young and future human beings will bear the brunt of climate harms, courts in cases such as Neubauer v. Germany and Amazon’s Future Generations v. Colombia have interpreted constitutional human rights provisions as recognizing a justiciable right to government climate action that is in line with the magnitude and the urgency of the problem.

The second norm relates to the legal competence of courts to enforce governments’ duties regarding climate action in general and emissions reduction in particular. The question of justiciability raises issues concerning the harmonization of (1) the protection of rights with deference for governmental policy discretion and (2) the duty of courts to provide remedies for rights violations with the principle of the separation of powers. Although common in human rights and public interest litigation writ large, those issues are compounded by the scale, temporality, and uncertainty that characterize the problem of global warming.

Unsurprisingly, judges have given a range of different answers to this question, in line with contrasting jurisprudential traditions on the redressability of rights violations by courts in different jurisdictions. However, regardless of outcome, courts in a majority of HRCC rulings have asserted their competence to review government climate policy and redress human rights violations stemming from it. Although granting governments latitude in setting climate goals and choosing policies to attain them, most courts have held that such decisions are not exempt from judicial review and that governmental discretion is not absolute. In cases like Greenpeace Nordic Association, judges have used the margin of appreciation doctrine to assess governmental policies’ impact on emissions reduction and conclude that the policies under challenge were within that margin.⁴⁵ In other cases, like In re Modification to Ethanol Fuel Rule (Mexico) and Urgenda, courts have used the same doctrine and ruled against the state, finding that the climate policies at issue unreasonably and disproportionately affected human rights and thus surpassed that margin.

In sum, the emerging norm regarding judicial review of climate action is that “courts have not considered the entire subject matter as a ‘no go’ area,” as the High Court of New Zealand concluded in Thomson v. Minister for Climate Change Issues⁴⁶ – a case on mitigation targets that, although not hinging on human rights arguments, summarized and built on a number of HRCC decisions. While adjudicators have recognized that governments have a wide margin of appreciation in dealing with the complexities of climate policy, they have tended to conclude that climate change is a regulatory and scientific issue that is amenable to judicial scrutiny based on national and international standards on climate change and human rights, as opposed to a political issue in which governments have full policy discretion. Indeed, the Paris Administrative Court in Notre Affaire à Tous v. France went as far as finding the French state responsible for moral damages stemming from its failure to take sufficiently ambitious climate action, noting specifically that “in view of the State’s wrongful failure to implement public policies enabling it to achieve the greenhouse gas emission reduction targets it has set itself, the applicant associations may claim compensation from the State for those wrongful failings.”⁴⁷

1.2.3 The Legally Enforceable “Fair Share” of Climate Mitigation

The final step of the ideal-typical case examines the compatibility of government policies with climate rights and duties. In some cases, the driving question is: What levels of ambition and urgency with regard to national emission reductions are compatible with such rights and duties? This is the question, for instance, at the core of the average European lawsuit (including the challenge to the European Union’s mitigation targets in Ferrão Carvalho v. Europe)⁴⁸ and the petition of a youth association to the South Korean Constitutional Court, which requests that the country’s low mitigation target be declared unconstitutional.⁴⁹ In other suits, rather than the level of ambition itself, plaintiffs challenge the consistency of government-authorized projects or policies with the mitigation target that the government has formally adopted through national or international law. This is the case, for instance, in the legal challenges to new airport runways in Vienna and London.⁵⁰ Most Global South lawsuits⁵¹ fit this second type, in that they do not challenge mitigation targets but rather specific government actions (or lack thereof) hindering progress towards those targets – from the omission of climate impacts in environmental impact assessments in South Africa and India⁵² to bureaucratic gridlock in Peru and Pakistan.⁵³

Both modalities of litigation raise complex questions about how to set and enforce a country’s level of mitigation ambition. The controversy over different criteria of equity for determining countries’ appropriate share of GHG emission cuts involves core issues of climate ethics and politics that are beyond the scope of this chapter.⁵⁴ Partly due to this complexity, litigants and courts in the typical HRCC case have tended to take a cautious approach by closely tying their claims and remedies to the ambition levels prescribed by the Paris Agreement and the IPCC.

This approach has been translated into two embryonic norms. First, with regard to a country’s share of emission reductions, HRCC cases have articulated a view that stresses individual states’ duties. States’ line of defense in mitigation lawsuits has hinged on the nature of the climate system as a public good. From this perspective, since emission reductions by one country will not make a dent in preventing global warming without other countries contributing their share, citizens have no justiciable rights-based claim to state climate action.

In contrast, litigants and courts have relied on a responsibility-based interpretation of the Paris Agreement. In this view, states have a duty to contribute their “minimum fair share” to emissions reduction, regardless of other countries’ actions. As noted, the determination of a country’s fair share has been guided by estimates stemming from the IPCC’s recommendations and reports.

The most explicit articulation of the “minimum fair share” norm can be found in the Dutch Supreme Court’s decision in Urgenda. According to the court, under the European Convention on Human Rights and the global climate regime, “the Netherlands is obliged to do ‘its part’ in order to prevent dangerous climate change, even if it is a global problem.”⁵⁵ The court bases its legal opinion on an interpretation of the UNFCCC whereby “all countries will have to do the necessary” to attain global emission targets, as well as on the generally accepted principle of international law according to which countries must avoid causing harm to others. “This approach justifies partial responsibility: each country is responsible for its part and can therefore be called to account in that respect”⁵⁶ in judicial forums. Using the heuristics of a “carbon budget” – the amount of GHG that is left for humanity to burn before surpassing the 1.5 degrees Celsius to 2 degrees Celsius threshold of global warming – the court concludes that “no reduction is negligible,” as all emissions contribute to using up the global budget, regardless of the size of the country or its emissions.⁵⁷

Although in a less elaborate way, courts have reasoned along comparable lines in other HRCC cases. The High Court of Ireland used a similar rationale to conclude that, “no country, particularly that of the size of this State, can tackle the [global warming] problem on its own. That, however, does not lessen the requirement to do what is necessary to achieve scientifically advised targets.”⁵⁸

As can be readily seen, if this norm takes hold in international and comparative climate rights law, it will create further incentives for litigation at the domestic level, as litigants in different jurisdictions would seek to exert bottom-up pressure on their own governments to contribute to global mitigation efforts, regardless of (or precisely because of) limited top-down pressure from intergovernmental negotiations. There is evidence that this process of transnational dissemination of judicial precedents and legal strategies is taking place. Litigants and courts in jurisdictions as diverse as Brazil, New Zealand, Norway, and South Korea are actively invoking some version of the “minimum fair share” norm to hold governments accountable for mitigation targets.

Nevertheless, this norm remains underspecified. Given that the meaning of “minimum fair share” varies according to the criterion of fairness used, this remains an open question in HRCC litigation (see Part II). One interesting case seeking to address this question is Duarte Agostinho v. Portugal, which was filed in the European Court of Human Rights by six Portuguese youth against a number of European states for their failure to take sufficiently ambitious climate action. The petitioners argue that the burden of proving that the respondent states’ climate policies are collectively consistent with the Paris temperature target should be on the states – the wrongdoers – as opposed to the petitioners – the victims of climate harms. In doing so, the petitioners seek to avoid a ruling that would fall within the low end of the necessary emissions reductions estimated by the IPCC but would collectively fail to limit warming to the Paris temperature target. By bringing this case in a regional court, moreover, the petitioners aim to secure a single ruling binding on most European states, thereby eliminating the potential for inconsistent domestic rulings on the adequacy of states’ emissions reduction ambition.⁵⁹

Moreover, this limitation has been partially compensated by a second emerging rule, which relates to remedies. In decisions issued in favor of the plaintiffs, litigants and courts have sought to take a cautious approach to mitigation remedies in order to strike a balance between climate rights and deference to government policy. Some lawsuits have focused on holding governments accountable to the mitigation pledges they set themselves, as in Torres Strait Islanders v. Australia⁶⁰ (which seeks to hold the government to the target recommended by its Climate Change Authority), Amazon’s Future Generations (where the Colombian Supreme Court enforced the government’s own targets regarding the reduction of deforestation), and Greenpeace Germany v. Germany (which unsuccessfully sought to hold the German government to its own 2020 target). Other lawsuits demand that governments increase their mitigation commitments but either limit themselves to asking the court to declare the existing target unconstitutional and mandate the government to determine a new target (as in Kim Yujin v. South Korea) or set the proposed target at the minimum level of emissions reduction that is required from the respective government, according to IPCC recommendations. The latter was the rationale behind the Urgenda ruling, which required the Dutch government to reduce the nation’s GHG emissions by 25 percent relative to 1990 levels by 2020, which sits at the lower end of the 25 to 40 percent range recommended by the IPCC and upholds the target that the government had adopted prior to 2011. Still other lawsuits challenge the most GHG-intensive policies or projects of a given country and request greater governmental scrutiny and transparency about their compatibility with the country’s stated mitigation targets. An illustration of this type of case is Zoubek et al. v. Austria, which challenges legislation that grants tax credits for air travel but not for rail transportation.

In sum, the norms emerging from HRCC litigation contribute to addressing some of the most complex and novel legal issues raised by the climate emergency – including the applicable corpus of international law, the status of the right to climate action and a livable climate system, and individual countries’ duties regarding contributions to climate mitigation. At least in the ideal-typical version that most lawsuits approximate, they fit the post-Paris governance framework. HRCC cases help provide this framework with some of the procedural and substantive parameters that it is missing and that are necessary for climate regulation to make substantial progress against global warming.

This does not mean, however, that the HRCC framework by itself can adequately handle the complexities of climate regulation, nor that human rights concepts and doctrines adequately address key outstanding issues in climate litigation. My study reveals interesting, if as of yet preliminary, potential blind spots and limitations of HRCC litigation. To these, I turn in closing.

1.3 Looking Ahead: The Potential and Challenges of Rights-Based climate Litigation

As mentioned in my Introduction to this volume and as shown by the figures on the rapid growth of HRCC lawsuits and petitions, rights-based climate litigation is an idea whose time has come. Although it is too early to systematically assess the impact of this trend on a range of relevant variables – from governmental and corporate climate action to climate social movements to the future of the Paris Agreement’s implementation – it is possible to extract some initial, forward-looking lessons about the potential of this type of legal action as well as its outstanding challenges.

The future-oriented implication of the argument and the evidence presented in this chapter is that the rights-based lawsuits that are most likely to contribute to climate action are those that explicitly incorporate the standards and regulatory logic of the global climate regulatory regime, namely, the Paris Agreement and the IPCC assessments. I argue that this type of HRCC litigation can provide material incentives for governments to put climate action at the center of their agendas, overcome policy gridlock, increase compliance and ambition, and foster transparency and participation in climate policy. Evidence of the potential of these incentives can be found in the impact on the aforementioned government climate commitments resulting from rulings such as those in Urgenda and Neubauer. Further, by publicly reframing the problem of climate change as a source of grievous impacts on identifiable human beings and as a violation of universally recognized norms, HRCC litigation can create symbolic incentives for governments and other domestic actors to put climate action at the center of their agenda and align their actions with the goals of the global climate regime.⁶¹ As courts adjudicate ongoing cases and new legal actions reach national and international tribunals, empirical case studies will be able to assess the material and symbolic potential of HRCC litigation.⁶²

Nevertheless, as with other types of litigation, HRCC litigation also has limitations that are worth bearing in mind when considering it as a strategic tool. For instance, rather than being an end in and of itself, the key contribution of the typical HRCC is that it helps set a regulatory floor upon which other forces – from social movement pressure to interstate negotiations – can build. This is the approach articulated in some of the most promising recent cases, such as the Torres Strait Islanders petition before the UN Human Rights Committee. Based on the aforementioned principles of international human rights law, the petition proposes a “minimum core obligation” that states need to meet in order to discharge their responsibility for climate mitigation. In addition to alignment with IPCC recommendations, this obligation includes procedural guarantees such as consistency (with previous state commitments, with relevant state policies, and with measures taken by states with comparable resources) and due process (adequate reason-giving and public participation).⁶³

Another limitation of HRCC litigation in the context of the international climate regime is its geographic reach. For very different reasons, rights-based litigation faces particularly difficult obstacles in the legal traditions of two of the key players in climate governance: the United States and China. However, the geographic spread of the ongoing wave of litigation suggests that it may be influential in some regions and countries that rank among the world’s largest GHG emitters, from Europe to the United Kingdom, Canada, Brazil, India, and Indonesia.

An important oversight that is evident in the universe of HRCC litigation is the dearth of cases on climate adaptation. This blind spot is particularly striking for two reasons. First, adaptation is the most pressing issue for a large majority of countries, including most of the Global South, which continue to contribute relatively small amounts of GHG and are already experiencing the brunt of the human impact of global warming. Second, the norms and frames of human rights lend themselves more easily to litigating adaptation – that is, measures designed to protect specific individuals and communities from the effects of forced displacement, economic disruption, health impacts, and other consequences of global warming that are already inevitable. By focusing on mitigation, HRCC litigation has overlooked half of the problem, one with urgent repercussions for most of the world’s population.

In terms of types of defendants, the most visible gap is the dearth of cases against corporations. As noted, only twenty-four climate lawsuits have ever been filed against corporations on human rights grounds. This is not entirely surprising, given the long-standing difficulties that human rights norms and concepts have had in dealing with non-state actors in general and corporations in particular. However, recent regulatory and socioeconomic developments may increasingly open the door for rights-based litigation against corporate actors. In the Casino case, for instance, litigants leveraged a combination of corporate law tools (specifically, the 2017 Corporate Duty of Due Diligence Law) and international Indigenous rights law to demand that Casino supermarkets take all necessary measures to exclude beef tied to deforestation and the grabbing of Indigenous territories from its supply chains in Brazil, Colombia, and elsewhere.

In the future, litigants will likely explore the use of the UN Guiding Principles on Business and Human Rights and other transnational regulatory frameworks (for instance, the OECD’s standards on corporate behavior) to hold corporations responsible for the human rights violations associated with their carbon emissions or to compel them to compensate governments or individuals for the costs incurred adapting to global warming.⁶⁴ In this way, litigants would effectively be translating into human rights language the claims against fossil fuel corporations that local governments in the United States have been advancing on common law grounds.⁶⁵ The human rights case, moreover, could be bolstered by growing evidence that some of these corporations have been aware of those harms for several decades and chose not only not to disclose it but also to actively lobby against climate action.⁶⁶ Indeed, a combination of these arguments underlies Greenpeace’s petition against carbon majors before the Philippines’ Commission on Human Rights; this strategy may well be replicated in other jurisdictions.

More broadly and conceptually, the nature of climate change exposes the shortcomings of long-held assumptions in human rights law and practice. The original articulation of these difficulties is also the clearest. In the first UN study on the implications of climate change, the Office of the High Commissioner for Human Rights concluded that “qualifying the effects of climate change as human rights violations poses a series of difficulties.”⁶⁷ Some difficulties have to do with causality, as it might be “virtually impossible to disentangle the complex causal relationships linking historical greenhouse gas emissions of a particular country with a specific climate change-related effect, let alone with the range of direct and indirect implications for human rights.”⁶⁸ Others relate to temporality, as “adverse effects of global warming are often projections about future impacts, whereas human rights violations are normally established after the harm has occurred.”⁶⁹

These issues are particularly challenging for traditional human rights strategies and concepts. As Kathryn Sikkink has observed, drawing on Iris Young’s theory of justice, the dominant paradigm in human rights advocacy is the “liability model of responsibility,” a backward-looking approach that focuses on determining guilt for individualized rights violations.⁷⁰ However, the liability model cannot adequately address structural injustices like climate change and economic inequality. Indeed, climate action requires a different, forward-looking approach to human rights. Following Young, the key question in this model is not so much “who is to blame?” as “what should we do to accomplish climate goals?” Forward-looking HRCC litigation contributes to answering the latter question by using what Sabel and Simon call “destabilization rights”⁷¹ – legal doctrines and concepts that may help disrupt dysfunctional institutional equilibria, like those common in climate policy, by prodding governments and other stakeholders to take more urgent and meaningful action against global warming.

My study of HRCC litigation highlights the initial signs of forward-looking concepts and doctrines that have the potential to deal with the difficulties associated with the causality and temporality of global warming. With regard to causality, HRCC cases have made progress in establishing the link between a country’s responsibility for GHG emissions and violations of human rights. As noted, litigants and courts have articulated an emergent “minimum fair share” norm, whereby countries are responsible for contributing to mitigation efforts, regardless of actions by other states. Relatedly, they can be held accountable for the human rights impacts associated with their GHG emissions. However, courts’ reticence to establishing a causal link between GHG emissions and plaintiffs’ individual human rights harms has been an important procedural obstacle in HRCC litigation. Several courts have thrown out cases for lack of standing, finding that the plaintiffs had not shown specific injuries from climate change, as in the challenge brought by citizens of Europe and other regions against the European Union’s mitigation targets in Ferrão Carvalho v. Europe⁷² and the challenge against the Swedish government’s sale of a coal-fired plant to a polluting energy company in PUSH Sweden v. Sweden.⁷³

This conventional and individualistic conception of standing ignores the nature of global warming as an omnipresent phenomenon affecting all human beings and indeed all forms of life on Earth. In contrast to it, recent decisions have articulated a new view of standing that better fits the nature of the problem. This is notably the case in the ruling of the German Constitutional Court in the Neubauer lawsuit, where the court held that the fact that climate impacts will affect virtually all persons living in Germany did not prevent the young plaintiffs from being affected in their own right and thus meant that they had standing to sue the government to demand more ambitious and urgent climate action.⁷⁴

The temporal dimensions of climate change also raise challenges to the linear, backward-looking temporality of human rights law. The most consequential human rights impacts associated with global warming will materialize in the future and will affect members of future generations, who are not recognized as rights-holders. Moreover, unlike other long-term human rights violations, the temporality of climate impacts is non-linear: delays are costly; the effects of inaction are compounded through time; some impacts are already irreversible; locked-in effects will continue to have adverse impacts on human rights even after climate action is accelerated (if it is ever accelerated); and tipping points and feedback loops may drastically worsen human rights violations in unpredictable ways.⁷⁵

Sensitivity to time may be one of the contributions of future climate-rights lawsuits and judicial decisions. Some of the existing cases offer useful pointers. In several of the rulings that deny the protection requested by the plaintiff, adjudicators explicitly tie their decision to present conditions and leave open the possibility of changing their views as global warming worsens. For instance, in the case against New Zealand brought by a climate migrant from Kiribati who had been denied asylum, the UN Human Rights Committee ruled against the migrant because sea level rise was unlikely “to render the Republic of Kiribati uninhabitable” for another “10 to 15 years,” but added: “given that the risk of an entire country becoming submerged under water is such an extreme risk, the conditions of life in such a country may become incompatible with the right to life with dignity before the risk is realized.”⁷⁶ Moreover, cases filed on behalf of young plaintiffs address the objection that climate harms entail future, as opposed to current, human rights violations by demonstrating that the dire impacts predicted for 2050 or even 2100 will be suffered by people who are already alive today.

With regard to the non-linear character of climate impacts over time, the Urgenda decision to enforce swift emission cuts invoked the cost of delays to dismiss the Dutch government’s argument that mitigation targets should be evaluated in 2030 as opposed to 2020. One of the clearest formulations of the non-linearity of climate change in HRCC litigation can be found in the dissent to the US Ninth Circuit Court’s decision to throw out the Juliana case on the basis of standing. “The majority portrays any relief we can offer as just a drop in the bucket,” wrote the dissenting judge.⁷⁷ “In a previous generation, perhaps that characterization would carry the day and we would hold ourselves impotent to address plaintiffs’ injuries. But we are perilously close to an overflowing bucket. These final drops matter. A lot.”⁷⁸

An even crisper and more consequential judicial pronouncement in this regard can be found in the German Constitutional Court’s ruling in Neubauer, which, to my mind, should be seen as the first comprehensively time-sensitive judicial decision on climate change. Mindful of the non-linear temporality of global warming, the court held that postponing climate action to a later day is constitutionally inadmissible inasmuch as it “irreversibly offload[s] major emission reduction burdens” onto the future and imposes “radical abstinence” on future generations.⁷⁹ Therefore, “the obligation to take climate action is accorded increasing weight as climate change intensifies.”⁸⁰ In a conceptual turn that addresses some of the aforementioned conceptual limitations of human rights, the court held that “fundamental rights [are] intertemporal guarantees of freedom.”⁸¹

In conclusion, the continued contribution of HRCC litigation to climate action will hinge on the dissemination of these and other jurisprudential innovations, as well as on the fate of ongoing efforts by litigants and courts to expand and update climate and human rights law in matters ranging from legal standing to the rights of future generations to legal liability for multicausal human rights harms. As the sociolegal literature on strategic litigation in other thematic fields has amply documented, it will also depend on whether litigants can successfully coordinate their law-centered strategies with the efforts of other advocates and movements that are at the forefront of the global mobilization for climate action, from youth organizations to Indigenous peoples to collectives of concerned scientists. And it will all need to happen at a much greater scale and faster pace if we are to match those of the most urgent challenge of our time.