CLIMATE LITIGATION
Rosa Mª Fernández Egea and Sofía Simou
1. Emergence, context and aim
More than twenty years have passed since the timid appearance of the first climate change cases. Within this period, the legal community has identified in climate litigation a useful tool for strengthening the public-private efforts in the global fight against climate change. Thus far, three distinct waves of climate litigation can be identified:
First-wave cases (prior to 2007) consisted primarily of administrative lawsuits against governments or agencies with the purpose of enhancing environmental protection standards. These cases took place mainly in the USA and Australia. Very often, they sought to integrate climatic considerations into the standard processes of environmental decision-making. In this sense, the earliest climate litigation cases fell under the broader concept of “environmental litigation”.
The second-wave cases (2007-2015) encompassed a series of socioecological conflicts that spread to other European countries, raising social awareness regarding the concept of litigation as a means to fill in the legal-political gaps in the absence of ambitious international action. These cases sought more systemic social and policy changes from the governments.
Third-wave cases (from 2015 to the present) feature greater expansion and diversification regarding the type of climatic demands, the volume of cases, the types of claimants/defendants and jurisdictions that are adjudicating on the matter (international, administrative, criminal, civil, labour, etc.). These third-wave cases seek to stimulate behavioural change in key players and include cases against the “major carbon emitters”. The most frequent aim in these processes is to assign responsibilities to the largest emitters or states´ inaction for the acceleration of climate change based on the evidence provided by progressive scientific studies confirming its human-induced nature and its links to the activity of certain countries and businesses. The most outstanding trends as well as the updated figures regarding the number of climate litigation cases brought to courts up to the current date can be consulted here (Setzer & Higham, 2025).
2. Scope of the climate litigation concept
No omni-comprehensive definition has been given thus far to climate litigation by literature with some authors adopting a broader and others a narrower approach to the concept (Savaresi & Setzer, 2021). The lack of consensus over the climate litigation concept may difficult the following tasks: a) applying the comparative law method to promote research on the subject; d) cataloguing cases into similar groups for their subsequent coherent analysis; and c) measuring the real impact of litigation on effective climate protection.
As pointed out by Setzer and Vanhala (2019), charting the concept of climate litigation has generated much debate with “as many interpretations of what is understood by ‘climate litigation’ as there are authors writing on the subject”. In their efforts to give meaning to the notion of ‘climate litigation’, the doctrine has differed on aspects such as:
a) Whether to include only cases that expressly raise issues of climate change policy or science or whether to also include cases motivated by concerns over other environmental issues (e. g., an objection against a coal plant on the grounds of its environmental impact); or over the consequences for not adequately addressing climate change (e. g., cases relating to costs and compensation expenses arising from extreme meteorological events);
b) Whether to focus on judgements issued by courts or to include other types of quasi-judicial decisions (for instance, conciliation decisions or opinions given by human rights committees);
c) Whether to include only those cases that are favourable to regulation or also those submitted by public or private agents challenging directly or indirectly regulatory measures (anti-regulation litigation) (Markell & Ruhl, 2021).
Given that climate change is a global problem that must be dealt with by a diversity of actors, instruments and disciplines, it is preferable to adopt, at least for the moment, a broad definition of climate litigation. Focusing exclusively on high-impact cases may divert attention from other important cases. There are several reasons for this. Firstly, since climate litigation takes place on different scales, cases on the lower levels of governance are just as important as the more prominent cases Secondly, climate change litigation “may involve all elements of good climate governance and not only the reduction of emissions” (Bouwer, 2018). Thirdly, a broad definition can be better when aiming to encompass climate change as a peripheral issue or motivating factor given that in some jurisdictions (especially in the global South) a significant number of cases involve approaches adjacent to climate change. Fourthly, because, without denying climate litigation’s capacity to change the rules and shape social awareness, in some cases it weakens appeasement or adaptation efforts. This may include cases that explicitly challenge climate action or cases whose principal purpose may not be such opposition but which aspire to an ecological transition aligned with social justice (climate anti-regulation).
As climate regulation increases, so will the number of ‘anti-regulation’ climate litigation cases. It is paradoxical that, in many cases, the arguments used by claimants to support ‘anti-regulation’ demands are similar to those put forward in “pure” climate cases. This shows that the plaintiffs in cases tagged as ‘anti-regulation’ climate litigation tend to allege the infringement of constitutional rights (such as the right to property, freedom, of enterprise, the right to free circulation, economic and social rights, etc.) These demands, in general, do not contest climatic action per se, but rather the manner in which it is carried out and its repercussions on other social rights (Simou, 2023).
However, the adoption of a broad view of climate litigation may turn out to be of little use internationally because legal action at this level is usually taken by States (and international organisations on the rare occasions when they have standing). Moreover, in the international field it is also important to pay attention to the pronouncements of international courts that do not resolve disputes (advisory opinions) but offer grounded opinions on the legal issues presented to them. There are also statements issued by other bodies that resolve disputes despite not being a court stricto sensu (UN Committees for human rights).
3. Constellations of claimants and defendants
Three basic scenarios can be identified in climate litigation (Sindico & Moïse Mbengue, 2021). The first scenario refers to claims against States for actions, inappropriate performance or omissions allegedly leading to increased GHG emissions or failure to adapt to climate change. The second scenario, deriving from a broader concept of climate litigation, includes claims against governments or other public bodies for authorising by infringing legal obligations activities that increase GHG emissions. The third scenario includes claims against private agents for activities leading to an increase in GHG emissions or against pension funds and other investment funds for unjustified or negligent investments.
According to Sindico & Moïse, the most frequent arguments raised in climate litigation cases are the following: human rights; failure to comply with obligations deriving from international law; tort law/breach of the duty to exercise due diligence; liability; judicial review; public trust doctrine; non-compliance with environmental obligations; criminal law motives; anti-competitive motives, fiduciary duties and breaches of codes of conduct.
From the viewpoint of international public law, cases generally deal with individuals especially affected by the adverse conditions caused by climate change (heat waves, wildfire, floods, etc.). This is possible on the international scale, largely due to the tendency to address climate litigation linked to the protection of human rights. This occurs because international climate litigation is brought before regional courts or quasi-judicial bodies responsible for the protection of human rights, at which individuals are granted standing.
When it is not the individuals that bring their case before international courts, it is the countries that are the most vulnerable to the risks of climate change that do so. This has happened regarding a series of consultative opinions brought to the attention of several international courts: the International Court of Justice, the International Tribunal of the Law of the See and the Inter-American Court of Human Rights. Moreover, international climate litigation has been brought before States or Governments (as it is usual in the international sphere, except in cases of international criminal responsibility which relies on individual standing). But these are specific States: those that can be held especially responsible for generating climate change or that possess the economic and technological means to mitigate it and invest in adaptation measures.
4. Theoretical challenges: procedural and substantive
Increasing climate litigation is posing a number of challenges on legal theory that can be divided into two categories:
(1) Procedural issues that may condition the admissibility by the courts of climate cases include: a) the conclusions reached by a Court in terms of justiciability to accept or dismiss its competence in the judicial control of climate decisions or inaction by other State powers; b) the legal requirements for standing which, when subjected to severe and unjustified restrictions, prevent cases from being adjudicated by the courts; and c) the question of causality or attribution when examined in the context of the admissibility conditions of the case.
(2) Material or substantive issues include: a) the scope and limits of judicial control under the principle of separation of powers with regard to climate matters; b) the treatment of scientific data by the judiciary in the context of scientific uncertainty (re-analysing the space that must be conceded to science and its representatives in interdisciplinary topics); c) the review of classical judicial theories such as the theory of procedure and the theory of fundamental rights in order to adapt them to the new social needs (rules on the burden or standards of proof); d) the way in which the judicial resolution of human rights climate cases is evolving, depending on the constitutional design and the level of protection of environmental rights in the different legal systems; e) the interrelation between climate litigation and the rights of nature theory (Kersten, 2017).
Leading cases:
Urgenda Foundation c. Países Bajos, Milieudefensie et al. c. Royal Dutch Shell, Neubauer et al. c. Germany, Klimaseniorinnen c. Suiza. A comprehensive list of climate litigation cases brought to date, with their corresponding documentation and listed by jurisdiction, country and type of claim, may be found on the database created by the Grantham Institute at LSE, in collaboration with the Sabin Center for Climate Change Law at Columbia Law School, available here.
Bibliography:
Bouwer K. (2018). The Unsexy Future of Climate Change Litigation. Journal of Environmental Law, 30, 483-506.
De Vilchez Moragues, P. (2022). Panorama de litigios climáticos en el mundo. In R. M. Fernández Egea & A. Macía Morillo (Dirs.), El derecho en la encrucijada: Los retos y oportunidades que plantea el cambio climático. Anuario de la Facultad de Derecho de la Universidad Autónoma de Madrid, 26, 349-381.
De Vilchez Moragues, P. (2022). Climate in Court: Defining State Obligations on Global Warming Through Domestic Climate Litigation. Edward Elgar.
Kersten J. (2017). Who Needs Rights of Nature? En A. L. T. Hillebrecht & M. V. Berros (Eds.), Can nature have rights?: legal and political insights (pp. 9-13). Rachel Carson Center for Environment and Society. Available in https://www.environmentandsociety.org/perspectives/2017/6/can-nature-have-rights-legal-and-political-insights
Markell D. & Ruhl J.B. (2021). An Empirical Assessment of Climate Change in Courts: A New Jurisprudence or Business as Usual. Florida Law Review, 64(1), 15-86.
Medici-Colombo, G. (2021). You cannot be serious!: Crisis climática, autorización de proyectos carbono-intensivos y su control judicial [Doctoral Thesis, Universitat Rovira i Virgili] http://hdl.handle.net/10803/672813
Setzer, J. & Higham, C. (2025). Global trends in climate change litigation: 2025 snapshot. Grantham Research Institute on Climate Change and the Environment, London School of Economics and Political Science. https://doi.org/10.21953/LSE.LH46LE9Y8SGI
Setzer, J. & Vanhala, L. (2019). Climate change litigation: A review of research on courts and litigants in climate governance. Wiley Interdisciplinary Reviews: Climate Change, 10(3), 1–19. https://doi.org/10.1002/wcc.580
Savaresi, A. & Setzer, J. (2021). Mapping the Whole of the Moon: An Analysis of the Role of Human Rights in Climate Litigation. https://dx.doi.org/10.2139/ssrn.3787963
Simou S. (2023). The emergence and potential of climate change litigation: methodological and theoretical legal challenges. European Review of Public Law, 35(1), 145.
Sindico F. & Moïse Mbengue, M. (Eds.). (2021). Comparative Climate Change Litigation: Beyond the Usual Suspects. Springer.