Published November 6, 2025
By Upasana Khatri, Senior Attorney with CIEL’s Climate and Energy Program.
On July 3, 2025, the highest human rights court in the Americas ruled unequivocally: the climate crisis is indeed a human rights emergency. In an Advisory Opinion that will reverberate across the Americas and beyond, the Inter-American Court of Human Rights (IACtHR) made clear that States and corporations have obligations under international law to address the causes and consequences of climate change. Failing to do so violates human rights.
The ruling is historic. The sweeping opinion, issued following the most participatory proceedings the Court has ever held, declared that States must take urgent, science-based, and equity-centered action on climate — not as a matter of choice, but as a legal duty. Together with the recent climate advisory opinions of the International Tribunal for the Law of the Sea (ITLOS) and the International Court of Justice (ICJ), the IACtHR decision offers a comprehensive framework to advance climate justice worldwide.
This opinion is already serving as a vital reference for courts, legislators, and advocates in the Americas. For communities fighting for survival, for future generations whose lives hang in the balance, and for ecosystems on the brink, it marks a turning point. The opinion offers a legal compass — and a moral one — charting a course where human dignity, environmental integrity, and intergenerational justice are not just ideals, but enforceable rights.
The Power of the Law
This landmark decision was the culmination of a process initiated in 2023, when Chile and Colombia submitted a joint request asking the IACtHR to clarify what the American Convention on Human Rights says countries must do in the face of the climate emergency. They asked the Court to weigh in on a range of issues — from adaptation, mitigation, and remediation of climate harm, to protections for particularly at-risk groups and environmental human rights defenders.
Advisory Opinions of the Court carry significant legal weight and provide authoritative interpretations of binding law that apply to all Member States of the Organization of American States (OAS), over 30 countries across the Americas. Because the fundamental rights at issue — such as the rights to life, health, personal integrity, and a healthy environment — are protected under many international and domestic legal frameworks, the IACtHR’s interpretation carries global significance not only for courts and policymakers in the Americas, but also for advocates and decision-makers worldwide.
In a world where climate impacts are escalating and political will is lagging, the IACtHR has drawn a clear line: protecting human rights means confronting the climate crisis.
Unpacking the IACtHR Climate Advisory Opinion
The Advisory Opinion affirms that States have a legal duty to prevent harm to the climate system, and that fulfilling it requires them to meet a high bar. This means adopting ambitious, science-based climate targets capable of preventing irreversible harm to the environment; developing mitigation and adaptation plans centered on human rights; and ensuring corporate accountability, transparency, international cooperation, and equity.
The IACtHR’s robust interpretation of what the American Convention on Human Rights and other relevant international law require in the face of the climate crisis has the potential to move the needle on climate justice in significant ways. Below are some of the Court’s transformative conclusions.
1. The strict prohibition on causing irreversible harm to the climate casts doubt on the lawfulness of fossil fuel expansion.
The Advisory Opinion concludes that the obligation not to cause irreversible damage to the climate and the environment constitutes a jus cogens norm: a prohibition of the highest order that cannot be set aside and by which all States must abide. According to the Court, dangerous human-driven interference with the climate system and the irreversible devastation it wreaks on the global commons constitutes an existential threat demanding a universal response . Building on its recognition that the autonomous right to a healthy environment is “a fundamental right for the existence of humanity” and a precondition for the enjoyment of other rights, the Court concludes that conduct causing “irreversible damage to the ecosystems that sustain life” is strictly prohibited.
The Court recognizes for the first time that the right to a healthy environment encompasses the right to a healthy climate. On that basis, it concludes that States have clear obligations to prevent climate damage, comply with international obligations to protect the climate system, and provide redress and integral reparation for harm resulting from the violation of those obligations.
By elevating the prohibition against climate harm to one of the highest, universal duties in international law, the Court extended its conclusions to all States. Enforcing the prohibition, however, requires determining which conduct qualifies as causing irreversible harm to the climate and the environment.
As the root cause of climate destruction, fossil fuel production and use is conduct that States are duty-bound to phase out. The Advisory Opinion broke the taboo that has long plagued international climate negotiations by expressly drawing on the best available science and naming fossil fuels as the main culprit of the climate crisis, underscoring the need for States to prioritize the “progressive reduction of GHG emissions” stemming from the sector. More generally, it called on States to encourage policies that “facilitate the transition of polluting sectors,” which necessarily encompasses the fossil fuel sector. The Court directly calls on States to eliminate “as quickly as possible” short-lived climate pollutants (SLCPs) like methane, which are generated in large part by oil and gas production and distribution.
In affirming the duty of States to conduct climate impact assessments prior to approving any high-emitting activities, the Court reinforces the growing judicial consensus that governments must consider downstream emissions from combustion before authorizing any fossil fuel production. The IACtHR made clear that such assessments must be performed at each stage of a project and based on up-to-date science. In the fossil fuel context, this means that States should require climate impact assessments before every phase of a fossil fuel project, including licensing, exploration, extraction, processing, transport, and decommissioning.
The ICJ’s own climate Advisory Opinion fills some of the gaps left by the IACtHR with regard to States’ duties to curb fossil fuel activity. Specifically, the ICJ emphasizes that failure of a State to protect the climate system from GHG emissions due to fossil fuel production, consumption, licensing, and subsidies “may constitute an internationally wrongful act which is attributable to that state”, triggering legal consequences. Read together, the IACtHR and ICJ climate advisory opinions lay crucial groundwork for challenging the permissibility under customary international law of new fossil fuel development, as well as the regulatory and financial enablers of the industry’s expansion, in the face of the escalating climate crisis.
2. Regulation of corporate climate action should reflect corporations’ respective responsibility for climate harm.
The Advisory Opinion requires States to differentiate corporate climate obligations on the basis of companies’ current and historical contributions to climate change. This equitable approach in addressing corporate accountability is aligned with the polluter pays principle — a longstanding tenet of international environmental law holding that responsible parties, not the public, should bear the cost of remediating environmental harm stemming from their conduct. In the context of GHG pollution and climate harm, companies with higher GHG-emitting activities should bear stricter duties when it comes to “operating conditions, tax burdens, contributions to just transition plans and strategies, investment in education, and measures of adaptation or to measures to address loss and damage”. Under the Court’s reasoning, fossil fuel companies are unequivocally among the businesses that States must subject to the strictest regulation, given their outsized role in driving the crisis. At the same time, the industry’s biggest climate culprits — an overwhelming majority of which are based in the Global North — should face even greater barriers to continuing “business as usual” and bear heightened legal responsibility for remedying climate damage and resulting human rights harm.
3. State responsibility for the extraterritorial human rights impacts of climate-destructive conduct within their jurisdiction or control necessitates expanded access to legal remedy when violations occur.
The Court reiterates that States have a duty to prevent significant environmental damage within or outside their territory, which entails that they’re on the hook if the climate impact of high-emitting activities within their jurisdiction or control results in human rights harm — even when it materializes abroad. In practice, this means that victims of climate-related harm may sue and seek reparations in countries where something the State did or did not do is causally connected to the harm.
With regard to fossil fuel activity, a State could thus be held responsible for climate harm stemming from fossil fuel consumption even if the GHG emissions and impacts occur abroad so long as precipitating conduct leading to the emissions, such as the production of the fossil fuels burned, was within the State’s control. Additionally, the Court clarifies that States can attribute legal responsibility to parent companies based on the GHG emissions generated by their subsidiaries or companies within their control; this should in turn translate to legal responsibility for a State that fails to adequately regulate the climate-destructive conduct of multinational companies that are registered or domiciled in its territory.
4. States must regulate corporate influence over public policy and climate disinformation.
One of the most novel aspects of the Advisory Opinion is its emphasis on corporate regulation and accountability. The Court holds that corporations have independent obligations to address the causes and consequences of climate change. It calls for stricter supervision on the part of States for companies that generate more GHG emissions. Additionally, it affirms States’ duty to investigate, prosecute, and punish corporate violators of environmental and human rights protections — among others.
However, where the Court breaks new ground is in confronting corporate capture and disinformation — conduct for which the fossil fuel industry has long avoided accountability. Implicitly acknowledging corporate capture of climate policy-making, the Advisory Opinion calls on States to combat greenwashing and undue corporate influence in political and regulatory spaces. In an era when corporate actors often understate their environmental footprint or promote so-called climate solutions that delay real action and pose new risks, this conclusion reinforces State duties to check businesses’ environmental claims and curb deception.
The Advisory Opinion reinforces that guaranteeing the right of access to information in the context of the climate emergency entails taking measures against climate disinformation. According to the Court, inaccurate information about the causes and consequences of climate change undermines the right to information and hinders democratic decision-making by distorting scientific consensus, creating public confusion, and ultimately preventing effective climate responses. Both States and private actors bear responsibility for ensuring public access to truthful, reliable climate information.
The Court missed an opportunity to acknowledge how the fossil fuel industry and other big polluters have exacerbated the climate crisis through their systematic denial of the science, deception around the true climate costs of their products, and obstruction of solutions. The Opinion nonetheless lays the foundations to hold major oil and gas companies, along with their government enablers, accountable for the climate damage caused not only by fossil fuel production and use, but by the industry’s obstruction and delay of timely climate action through decades of disinformation and deception. Additionally, the Court’s conclusion that climate information is of public interest requiring maximum disclosure could bolster challenges to governments or fossil fuel companies that continue to withhold relevant climate information based on claims of business confidentiality, or that invoke national interest or security reasons to shield oil and gas projects from scrutiny.
5. Enforcing a differentiated approach to protecting the rights of those at greatest risk of climate harm ensures that climate action and justice do not replicate structural inequities.
Recognizing that climate change is a threat multiplier whose impacts fall disproportionately on historically marginalized populations and people in vulnerable situations, the Advisory Opinion’s approach to climate action centers equity. The Court calls on States to apply differentiated measures of protection reflective of the distinct vulnerability certain groups face to climate-related risk and disasters — including Indigenous Peoples, women, members of the LGBITQ+ community, children and future generations, and persons with disabilities — and how intersecting identities and factors may exacerbate vulnerabilities. Among the differentiated measures States must undertake is ensuring physical, informational, and procedural accessibility to climate decision-making and response.
Many of the Court’s pronouncements on access to justice are grounded in overcoming structural inequities and procedural barriers that put climate justice out of reach of those in some of the most dire conditions. Presuming a causal link between GHG emissions, climate degradation, and resulting harm could minimize claimants’ burden of establishing causation in some cases. Given asymmetries in access to climate science and the affordability of litigation for parties, the Court suggests, reversing the burden of proof may be warranted to guarantee access to justice. Such an approach would be especially important for plaintiffs who are already at a disadvantage financially, given the high costs associated with accessing climate data and science and hiring expert witnesses — two resources that are already difficult to come by in Latin America and the Caribbean, yet often critical for success in complex cases. Additionally, in affirming the value of Indigenous, traditional, and local knowledge to climate action, the Opinion should encourage courts to recognize the credibility and probative value of evidence derived from these knowledge systems in litigation and expand their acceptance in climate cases. Indeed, expanding the types of evidence accepted in climate cases will help overcome procedural hurdles, thus enabling more people to seek remedies for climate-related losses.
Among the actors doing the most to advance effective climate action, accountability, and justice are environmental human rights defenders. The Advisory Opinion recognizes their work as invaluable to the fight against climate change and emphasizes their entitlement to protection and justice. The Court declares that States owe a “special duty of protection” to investigate, prosecute, and punish crimes committed against them and ensure they can operate without fear of reprisal or criminalization — including for taking legal action in pursuit of climate justice. Amidst rising authoritarianism and crackdowns on civil society, the Court importantly emphasizes that strengthening democratic rule of law is fundamental to protecting human rights in the climate emergency, and that environmental human rights defenders are essential to that effort.
6. The Advisory Opinion reinforces domestic court rulings recognizing Nature as a subject of rights.
For the first time, the Court affirms the importance of Nature as a subject of rights entitled to legal protection, aligning itself with emerging jurisprudence and constitutional reforms in several Latin American countries that recognize the rights of rivers, forests, and ecosystems. By placing nature’s integrity at the center of legal interpretation, the Court elevates the duty of States to act not only in defense of human populations, but also in defense of the ecosystems that sustain all life. This reflects a paradigm shift from viewing the environment merely as a resource to seeing it as a legal subject worthy of protection in its own right.
A Blueprint for Action
The Inter-American Court’s climate Advisory Opinion is not just a legal document — it is a call for justice in the face of crisis. It affirms that climate justice is human rights justice, and that effective solutions must be built on law, science, equity, and accountability.
Courts in the Americas are already responding. Less than a month after the Advisory Opinion was issued, a court in Colombia recognized the legal personhood of the Santurbán páramo and its surrounding areas, directly citing the Advisory Opinion’s affirmation of States’ duty to protect nature as a subject of rights. In August, a federal court in Brazil repeatedly cited the opinion in a case concerning the concession of the Candiota coal mine in the state of Rio Grande do Sul, stopping the project from moving forward until climate considerations were assessed and incorporated into the environmental licensing process.
The question now is whether other courts and policymakers will follow suit. If implemented with courage, this ruling can help bend the trajectory of our future — away from impunity, injustice, and collapse, and toward accountability, resilience, and hope.
