Inter-American Court of Human Rights: There is a Human Right to a Healthy Climate

On 3 July 2025, the Inter-American Court of Human Rights (“IACHR”) handed down its advisory opinion on the climate emergency and human rights (the “IACHR Opinion”) which, among other conclusions, finds that there is a human right to a healthy climate and that States have obligations to protect and uphold that right. Among these obligations include the expectation to regulate businesses and oversee that they mitigate their contribution to climate change. 

The IACHR Opinion is the second advisory opinion from an international court on State duties in the context of climate change. In May 2024, the International Tribunal on the Law of the Sea released its advisory opinion on States’ obligations to preserve the oceans from the effects of climate change and, after the publication of the IACHR Opinion, on 23 July, the International Court of Justice issued its unanimous opinion that States can be held legally accountable for the harm they cause to the climate (the “ICJ Opinion”). More detail about the ICJ Opinion can be found in our article.

Background

The IACHR is an autonomous judicial body which applies and interprets the American Convention on Human Rights (the “Convention”), as well as other Inter-American human rights treaties. While the Convention has been ratified by the 35 members of the Organization of American States (“OAS”), not all member states – including the USA and Canada – have recognised the jurisdiction of the IACHR. 

On 9 January 2023, Chile and Colombia submitted a request to the IACHR for an advisory opinion on the obligations of States to respond to the climate emergency under international human rights law. The IACHR’s findings, while not binding, are illuminating and far-reaching. In its lengthy opinion, the IACHR considers the factual background to the climate emergency and the international response, as well as the interpretation of the Convention and other treaties which were the subject of the request. 

IACHR Opinion

Among the key findings of the IACHR Opinion, the following are of particular interest:

• Right to a healthy climate: The IACHR Opinion found that the right to a healthy climate is an essential part of the right to a healthy environment and that its protection should be understood as a specific objective within the framework of environmental protection. The IACHR stated that damage to the climate is distinct from other forms of environmental damage and therefore the right to a healthy climate is an independent right, a recognition which it says aligns with the evolution on international human rights and environmental laws.
   
• Duty to prevent irreversible harm: The IACHR Opinion affirms that States have an obligation to counter the human causes of climate change and protect people under their jurisdiction from climate impacts. This obligation derives from the right to a healthy climate itself, a right on which numerous other fundamental rights depend.[1] IACHR stated that even States which are not party to the climate treaties are required by international law to prevent significant harm to the climate: it defined the obligation not to cause irreversible damage to the climate as jus cogens, a fundamental and universally accepted binding principle of customary international law, from which no State can deviate.
   
• Obligation to carry out due diligence: An extension of the duty not to cause harm is the requirement to carry out appropriate due diligence to counter anthropogenic climate change and protect people, especially the most vulnerable, from its impacts. Among other things, States have obligations to identify and assess the climate risks they face, adopt proactive and ambitious measures to avoid worst-case climate scenarios, and monitor the impacts of any measures adopted. 
   
• Specific rights of nature: The IACHR Opinion recognises that nature and its components are independently subjects of rights, representing the interdependence between human rights and the environment and the growing trend to increase protection of ecological systems. The IACHR states that States have a positive duty to adopt measures, consistent with the best available science and indigenous knowledge, to ensure the protection and restoration of ecosystems.
   
• Presumption of causal link: The IACHR acknowledges the difficulty in establishing a direct causal link between actions or omissions of a State and the decline of the climate system. It therefore encourages the possibility of presuming a causal link between GHG emissions, the climate decline, and the risks posed to people and nature. The IACHR calls for judicial flexibility to remove procedural barriers for victims, potentially encouraging more innovative paths to litigation.

This list is by no means exhaustive. The IACHR Opinion, which spans more than 200 pages, also highlights: the importance of considering the people who are most vulnerable in society; States’ legal duty to protect human rights defenders; that procedural rights underpin the right to a healthy climate; the obligation to disseminate scientific information and tackle disinformation. It makes clear that States’ obligations in the face of the climate emergency are far reaching and varied. 

What does this mean for companies?

The duties identified in the IACHR Opinion apply directly to States, rather than private actors. However, the IACHR recognises that companies have a “fundamental role” in addressing climate change. The IACHR considers that there will be a trickle-down impact as States strive to meet their obligations, including through regulating businesses in line with the UN Guiding Principles on Business and Human Rights and requiring greater transparency from businesses on the climate impacts of their activities. The IACHR considers that States should establish “differentiated” obligations on companies commensurate to their current and historical contribution to GHG emissions, which could relate to business operating conditions, tax burdens, or addressing loss and damage, for example.

The last year has seen considerable uncertainty around sustainability regulation which had only recently been introduced,[2] a trend which seemingly goes against the conclusions drawn in the IACHR Opinion that States have legal obligations to protect against climate change and could be held liable for failing to do so. While the IACHR Opinion and opinions from other international courts are only advisory and therefore not binding, they are important indicators of where international judicial thinking stands and the increasing importance of climate in the context of human rights. Both the IACHR and ICJ Opinions are likely to be drawn upon by climate activists in climate litigation at international and domestic levels. For now, businesses are unlikely to feel any immediate impacts as a result of these opinions, but the policy-focused tone and the clear articulation of existing legal rights in both texts may sound a cautionary note for States as they review how to respond to the growing climate emergency.

[1] The fundamental rights include the rights to life, personal integrity, health, non-discrimination, private and family life, private property, housing, freedom of residence and movement, water, food, work and social security, culture, education and a healthy environment.

[2] For more information see our blogs on the Omnibus here and here.