A member of the Guarani-Kaiowa ethnic group (C) attends a hearing on the responsibility of states in the face of climate emergencies, organised by the Inter-American Court of Human Rights
Source: Getty

A Seminal Case for Climate Litigation

Climate change presents states with new obligations. Chile and Colombia are asking what those are.

Published on June 26, 2024

“We are facing a climate emergency with a devastating potential for life on earth,” write the governments of Chile and Colombia. That is why they are asking the Inter-American Court of Human Rights (IACtHR) to “clarify the scope of State obligations, in their individual and collective dimension”—the obligations that come with governing in an age of climate crises.

This historic request to the court is just the latest example of states asking international legal bodies to guide their actions. And the court’s advisory opinion in response to the request could be one of the most important so far, shaping policy on climate change, human rights, and climate mobility in the Americas and beyond. 

The IACtHR is one of the world’s three regional human rights tribunals, alongside the European Court of Human Rights and the African Court on Human and Peoples’ Rights. Based in Costa Rica, the IACtHR was established in 1979 by members of the Organization of American States as an independent body to apply and interpret the American Convention on Human Rights. The court pursues its given mandate in three main ways. First, it hears and resolves contentious cases involving alleged human rights violations and supervises its judgments. Second, it issues provisional measures, which have a preventive nature and are meant to avoid irreparable harm to people. Notable examples of these measures include those granted to safeguard life in the context of serious prison conditions, as demonstrated by the case of Urso Branco prison, in which the court ordered Brazil to adopt “all necessary measures to protect the life and personal safety of all persons detained.” The court also ordered “seizing all weapons that are in the hands of the inmates.” Another notable example of such measures is the case of the Indigenous peoples of Mayagna Awas Tingni in Nicaragua, in which the court asked the state to protect the use and enjoyment of property of lands belonging to the community as well as the natural resources existing on those lands. Third and, finally, states can ask the court to provide guidance regarding the interpretation of various treaties concerning the protection of human rights in the Americas.

It is this latter advisory function that Chile and Colombia are now asking the court to perform. This is not surprising, as both states’ left-wing governments are seeking to position themselves as world leaders on climate action. In fact, efforts in this regard began under prior administrations, and they currently involve not only taking new approaches to international climate change policy but also achieving ambitious domestic agendas.

In the case of Chile, these efforts include (1) the adoption of a framework law on climate change, which incorporates a binding goal of net-zero emissions by 2050; (2) the presentation in 2020 of an innovative approach that ties nationally determined contribution (NDC) commitments made under the Paris Agreement with the United Nations’ Sustainable Development Goals, including achieving a process of just transition for the decarbonization of the energy matrix; and (3) the recent launch of Chile’s Green Hydrogen Action Plan 2023–2030, a comprehensive strategy to promote development of its green hydrogen industry.

In Colombia, climate action has taken a prominent place, cutting across different areas of government. In 2017, the state adopted a national policy on climate change; and, in 2021, it passed a climate action law, in which NDC commitments were elevated to national norms and goals were established on carbon neutrality.

Internationally, Chile and Colombia argue that countries are facing persistent challenges as a result of climate change, including droughts, floods, landslides, and fires. They say there is an urgent need to formulate responses based on the principles of equity, justice, cooperation, and sustainability—all through a human rights–based lens. The states have asked the court to provide “guidelines for the development of local, national and international policies and programs—in keeping with the commitments made under the American Convention and other human rights and environmental treaties” that are valid for “both the requesting countries and the other countries of the region.”

The Rise of Climate Lawsuits

To understand the specifics of the two states’ request, it is useful to look at the global context. This request is part of a recent global trend of climate litigation. Two other noteworthy advisory opinion requests regarding climate change were recently filed before major international tribunals. In December 2022, the Commission of Small Island States on Climate Change and International Law (COSIS), under the leadership of Tuvalu and Antigua and Barbuda, turned to the International Tribunal for the Law of the Sea (ITLOS) to seek clarification regarding parties’ obligations to the United Nations Convention on the Law of the Sea (UNCLOS) in preventing, reducing, and controlling pollution of the marine environment in order to preserve and protect it from climate change impacts. A few months later, in March 2023, the General Assembly of the United Nations, following an initiative led by Vanuatu, unanimously adopted a resolution requesting an advisory opinion of the International Court of Justice (ICJ) on states’ obligations under international law in respect of climate change and on the legal consequences for states that have caused harm to the climate system, to other states (in particular small island ones), and to the people, including future generations.

On May 21, 2024, in response to COSIS’s request, ITLOS delivered an opinion to advise on climate change and international law. In the long-awaited advisory opinion, the tribunal addressed several key issues on the application of UNCLOS in the context of climate change. Among those, the tribunal, relying significantly on the authoritative works of the Intergovernmental Panel on Climate Change, confirmed that “anthropogenic GHG emissions into the atmosphere constitute pollution of the marine environment,” as defined by the convention and with the obligations that derive from that. It also affirmed that state parties to the convention must take all necessary measures to prevent, reduce, and control marine pollution from emissions, as well as to harmonize their relevant policies. It further stressed that states are obligated to also reverse degraded ecosystems to regain ecological balance. And notably, the tribunal stated that UNCLOS obligations are not necessarily satisfied “simply by complying with the obligations and commitments under the Paris Agreement.” There are 168 parties to this convention, and 164 of them are UN member states.

Other courts have also been hearing more individual cases to help determine violations related to the impacts of climate change. In April 2024, for example, in a landmark case against Switzerland, the European Court of Human Rights ruled that weak government climate policies violated fundamental human rights. The court found that Switzerland had failed to comply with its duties to stop climate change and, in doing so, had violated the right to family life of a group of elderly women. More than 2,000 women argued that they are now more likely to die in heatwaves, which have become more frequent and more intense extreme due to human-induced climate change.

Domestic courts are also doing their share: for example, the Federal Constitutional Court in Germany found that the legislation on climate protection was partly unconstitutional because it was insufficient to protect future generations. And Colombia’s highest court has also ruled that the impacts of climate change—both in terms of sudden onset hazards (for example, hurricanes and floods) and slower onset processes (for example, droughts, ocean acidification, and sea-level rises)—can be legally considered causes of forced displacement and therefore place an obligation on the state. With this ruling, the Colombian court has likely crafted one of the most comprehensive responses to climate displacement to date. The response includes (1) provision of the necessary humanitarian assistance required to guarantee people’s rights to food, potable water, housing, clothing, health, and sanitary services; and (2) preparation of a risk and vulnerability assessment of the land to determine whether mitigation for future events can take place, and, if this is the case, then the court calls for the safe, dignified, and sustainable return of displaced individuals, as well as access to adequate housing and support to engage in agriculture activities similar to ones carried out before the displacement occurred. If flooding risks cannot be mitigated, then the court says that the government must ensure the relocation and safety of displaced individuals, as well as sufficient access to dignified housing and social programs in a way that guarantees them a source of income in accordance with their needs and cultural identity. The court also invites the ombudsman to monitor the progressive restitution of their rights as internally displaced persons. More broadly, it urges the Colombian Congress and the national government to develop a legal framework to address environmental displacement and, in the meantime, address this issue ensuring the minimum guarantees for those forced to move due to climate and environmental reasons. In the wake of this ruling by the highest national court, the Colombian government now wants guidance from the regional IACtHR.

Why the IACtHR Stands Out

While various courts around the world have been making strides in recognizing the different duties of states in the context of climate change, Chile and Colombia’s advisory opinion request to the IACtHR could have especially wide-ranging effects. The request, made in January 2023, is significant for four main reasons.

First, the request highlights the need for a rights-based approach to climate change. As such, Chile and Colombia seek clarity on various aspects concerning states’ human rights obligations in relation to the climate emergency, including children’s and women’s rights, environmental defenders, Indigenous peoples, access to justice, as well as human mobility. In their request, they asked the court to pay special attention to “the differentiated impacts of this emergency on individuals from diverse regions and population groups, as well as on nature and on human survival on our planet.” Additionally, this request reaffirms that climate change is not solely an environmental issue but also a matter of human rights. For example, the request asks the court to analyze concepts, such as “common but differentiated responsibilities,” which is a principle described in the Paris Agreement that expresses that all states have a responsibility to address climate change but some should bear a bigger burden. Analyzing this concept in light of states’ obligation under human rights law could result in innovative international law development. 

Additionally, the request to the IACtHR is the only one of the three major international cases mentioned here to specifically include a question on human mobility and climate change. It is included in the section regarding states’ shared and differentiated obligations and responsibilities, and it specifically asks about the principles that should guide the states’ individual and coordinated measures to deal with involuntary human mobility exacerbated by the climate emergency. The impacts of the climate emergency are profound, and even if harmful greenhouse gas emissions ended today, many communities would still face significant livelihood challenges and/or be forced to move because of damages that have already been sustained to the environment. This situation presents a pivotal opportunity to elaborate on the obligations and duties of states within the human rights protection framework of the inter-American system, including rights to food, water, health, adequate housing, nationality, and self-determination, with attention to preserving people’s cultural needs in order to protect their human rights when forced to relocate due to the impacts of climate change.

Second, the IACtHR has a progressive norm development tradition based on its approach of placing the experience of victims at the center of judicial interpretation. This has already resulted in pioneer jurisprudence on the relationship between the environment and human rights: there is now recognition that these two areas of international law, which had been operating in a parallel track, are, in fact, interconnected. In a prior advisory opinion, the court emphasized that the right to a healthy environment is central to the enjoyment of other fundamental rights and that “states have the obligation to prevent significant environmental damage within and outside their territory.” Moreover, in a recent case of the community of La Oroya v. Peru, the court recognized “that environmental degradation can have severe consequences for the enjoyment of human rights, which is why a healthy environment is a fundamental right for the existence of humanity.” As David Boyd, the United Nations special rapporteur on human rights and the environment, put it, “The Inter-American Court’s decision is the strongest and most comprehensive judgment of any regional human rights court to date.”

Third, the IACtHR’s process differs vastly from that of the other two international tribunals, particularly in its participatory and democratic approach. Even though the ICJ can draw on a wider scope of international law resources to inform its opinion, the court proceedings are much more restrictive. The IACtHR allows member states and other interested parties (for example, civil society organizations, universities, and experts) to submit written observations. The American Convention on Human Rights allows any institution or person to submit an amicus curiae brief, and there is no geographical constraint when it comes to who can present information. Next, the court invites those who filed submissions to complement them with oral arguments in a series of public hearings.

Oral arguments about Chile and Colombia’s request represented a unique historic moment. In Barbados in April 2024, for three full days, a six-judge panel listened attentively to the oral arguments presented by various states, scientists, members of academia, renowned jurists, international organizations, civil society, youth, as well as representatives from communities who are experiencing firsthand the impacts of climate change. The judges asked relevant questions and referred to the various written documents, they pushed the presenters to further elaborate on their recommendations, and they allowed sufficient time for speakers to answer the questions. Among those presenting was twenty-year-old Kalālapa Winter, a plaintiff in the Navahine F. v Hawaii Department of Transportation case. The presenters argued that the Hawaii Department of Transportation is illegally emitting excessive levels of greenhouse gases, which violates people’s constitutional rights. Winter shared with the court her concern about how slowly governments are reacting and warned that “the harm they are experiencing “will only become more severe and irreversible without the lack of science-based action to address climate change.”

From May 24 to 29 in Brazil, the court then held public and live-streamed hearings, with a different set of 116 delegations. Overall, the court received 262 written observations from more than 600 participants. The court will now spend the next six to nine months using the information received to craft a thoughtful, judicial, and informed opinion.  

Fourth, Chile and Colombia’s request demonstrates states’ commitment to the international community. This twenty-one-question request submitted by two Latin American states not only represents a vote of confidence in the court and its relevance to help address this global challenge, but also represents an example of the best tradition in international law and the development of international norms. It is remarkable that, for the almost fifty years of the court’s existence, states in the Americas have often resorted to asking the court for guidance when in doubt about their obligations in relation to the protection of human rights. Although advisory opinions are not binding in nature, they have legal authority and weight in prescribing what states ought to do under international law. In fact, an advisory opinion is one of the main tools to clarify international law and a means for its development. In the case of the Americas, the IACtHR has issued thirty opinions and has examined a wide range of issues, such as states of emergency, death penalties, freedom of expression, equality, and nondiscrimination, among many others. The court has been an important source for the development of constitutional rights in legal systems throughout the region; and it is undisputed that the opinions of the court, which is viewed as a legitimate body that interprets the American Convention on Human Rights, enjoy recognition by the states. Various domestic high courts have been able to progressively realize fundamental rights by using the court’s interpretation. The Constitutional Court of Ecuador, for example, drew on the arguments of the IACtHR’s Advisory Opinion OC-5/85 to determine the nature of the right to freedom of expression. Various domestic bodies have also used the advisory opinion as a useful tool for policymaking.

Only the Beginning

The impacts of the climate emergency are not being adequately addressed, largely due to the lack of sufficient action by states and the voluntary nature of climate negotiation. Some provisions of the Paris Agreement do not include legal obligations, particularly those provisions that relate to states’ voluntary cooperation to reach their climate targets. And therefore, states can lower or eliminate their targets without consequences. It is in this context that vulnerable states and communities, particularly those that are bearing the brunt of climate change effects, are increasingly seeking legal recourses to address climate change, particularly when they feel that their voices are not being sufficiently represented in international talks. Throughout its history, the IACtHR has built on ample experience in establishing legal obligations and making concrete recommendations for states to ensure the protection of human rights. Therefore, the IACtHR is now well placed to analyze human rights law together with the relevant environmental law concepts and take a significant step towards construing what these duties and obligations are in light of this crisis. By recognizing what is at stake and the obligations of states, the IACtHR can provide a framework for addressing climate change in a manner that respects and protects human rights, in particular for those who are and will be disproportionally impacted.

Overall, the recent court proceedings emphasize the importance of international and regional cooperation in addressing the global challenge of climate change. They are evidence that no country can tackle this issue alone and that collaboration and support between states are vital to effectively address the impacts of climate change on human rights.

Carnegie does not take institutional positions on public policy issues; the views represented herein are those of the author(s) and do not necessarily reflect the views of Carnegie, its staff, or its trustees.