Inter-American Court of Human Rights delivers Advisory Opinion on the obligations of States to respond to the climate emergency

On 3 July 2025, the Inter-American Court of Human Rights (the “Court”) issued its opinion on the obligations of States to respond to the climate emergency under international human rights law, finding that States have a duty to mitigate and address environmental harms threatening human rights (such as climate change), including by adopting national laws, policies and actions (the “Opinion”). 

Key takeaways

• The Court affirmed the right to a healthy environment, stating this includes the right to a stable and healthy climate. 
• States have an obligation to adopt necessary effective measures to prevent serious or irreversible damage to the environment (including climate change) and to prevent connected human rights impacts.
• To prevent and mitigate climate risks, States must adopt a standard of enhanced due diligence based on scientific evidence. 
• States have specific duties to prevent harm and ensure the protection of vulnerable groups, who might face disproportionately severe impacts from climate change.
• Finally, the Court emphasises the role businesses must play in addressing the climate emergency and places a duty on States to regulate companies’ actions to avoid human rights abuses arising out of dangerous climate change. 

The role of the Inter-American Court of Human Rights and putting the opinion into context

The Court is the highest human rights court in the Americas region and one of three regional human rights courts in the world (together with the European Court of Human Rights and the African Court of Human and Peoples’ Rights). 

It is an autonomous legal institution whose objective is to interpret and apply the American Convention of Human Rights (“ACHR”), and one of the Court’s key functions is to issue advisory opinions at the request of member states of the Organisation of American States. 

This Opinion is the second of four advisory proceedings at international courts, clarifying state obligations in relation to climate change:

• In May 2024, the International Tribunal for the Law of the Sea (“ITLOS”) issued an advisory opinion confirming that all anthropogenic greenhouse gas emissions constitute marine pollution and clarifying that States must take all measures to prevent, reduce and control emissions and to protect and preserve the marine environment against the impact of climate change. 
• On 23 July 2025, the International Court of Justice in The Hague (“ICJ”) presented its opinion on the obligations of States in respect of climate change (separate blog post to follow).  
• And, in May this year, a petition was filed with the African Court on Human and Peoples’ Rights for an advisory opinion on the obligations of African Union member states in the context of climate change. The timing for when this final opinion will be issued is currently unclear. 

While these opinions are not legally binding, they are authoritative interpretations of legally binding obligations and carry substantial legal and moral weight. This contrasts with court decisions on similar topics, including the 2024 European Court of Human Rights’ ruling that States that are Parties to the European Convention of Human Rights have an obligation under Article 8 to provide protection against adverse effects on human health from harmful effects and risks caused by climate change, which is binding on all States that are Parties to that Convention (see our blog post). 

Brief recap – Chile and Colombia’s submission

On 9 January 2023, Chile and Colombia submitted a request to the Court, asking it to clarify the scope of State obligations to respond to the climate emergency under international human rights law (in particular the ACHR). 

The request highlighted that both countries now faced daily challenges arising out changing weather patterns due to climate change and that these effects were overwhelmingly being felt in the most vulnerable communities (for example, children and indigenous peoples, amongst others). It also referred to a 2017 advisory opinion from the same Court, requested by Colombia, in which the Court recognised (for the first time) the right to a healthy environment and the relationship between environment and human rights. 

The Court reformulated the questions posed by Chile and Colombia into three main buckets: (i) the obligations States owed (and the scope of these obligations) to respect, guarantee and adopt necessary measures to make effective substantive rights; (ii) procedural rights; and (iii) rights of vulnerable persons or population groups. 

Right to a healthy environment

Firstly, it is important to note that the Court affirmed its recognition of the right to a healthy environment as an autonomous right, meaning the environment and its component parts (forests, rivers, seas, etc.) are protected in their own right, even absent evidence of risk to individual persons, and concluded that this includes a right to a healthy climate. 

From this, the Court derived a number of State obligations, in particular an obligation to address the causes of climate change and mitigate greenhouse gas ("GHG") emissions (in particular from fossil fuel use, agriculture, livestock, deforestation, and other land uses). 

State obligations to respect, guarantee, and adopt human rights measures

The Court found that even in the absence of scientific certainty, States are obliged to adopt necessary effective measures to prevent serious or irreversible damage to the environment (including climate change) and to prevent connected human rights impacts. 

The Opinion clarified that the duty to “guarantee” human rights under the ACHR is an obligation of means or conduct (rather than result). However, States must act in accordance with the standard of enhanced due diligence and could be required to adopt domestic regulatory measures if necessary. The Court noted this duty implies that all government bodies and, in general, all structures through which the exercise of public powers is manifested should be organised so that they are capable of legally ensuring the free and effective exercise of human rights (including through the regulation of private, third-party actors like businesses).  

The Court also found that States must refrain from any rollback of climate or environmental policies that affect human rights unless any such rollback is exceptional, duly justified (on the basis of objective criteria), and necessary and proportionate. 

States must also cooperate, in good faith, to protect against environmental damage, taking into account differing technological and economic capacities, and that this obligation is not restricted solely to situations of transboundary threat or harm, but has special relevance when addressing the causes and impacts of climate change. This means that cooperation must consider factors such as the differences amongst States, their capabilities and their responsibilities (implying factors relevant to a “just transition” should be taken into account). 

Procedural rights

The Court affirmed the importance of procedural rights (e.g. the right to access to justice and information) in the context of the climate emergency. 

In particular, the Court affirmed States’ duties to disseminate the benefits of science and emphasises the existence of local, traditional, and indigenous knowledge. It concluded that States must take measures to protect, and support the collection of, this knowledge and take all necessary measures to respect and protect the rights of indigenous peoples. 

Protecting vulnerable communities

Throughout the Opinion, the Court acknowledges that, both in the Americas and globally, vulnerable population groups (including children, environmental defenders, women, indigenous peoples, Afro-descendants, and others) might face disproportionately severe climate change impacts. The Court noted States have specific duties to prevent harm and ensure the protection of these groups. 

What does this mean for businesses? 

The Court notes companies have a fundamental role in addressing the climate emergency. It considers States’ obligations to adopt domestic legislative and other measures to prevent, investigate, punish, and guarantee reparations for human rights abuses by State and third-party actors as, in short, an obligation that must be fulfilled by companies and regulated by the States. 

While the Court considers all businesses to have human rights responsibilities, it acknowledges the scope of this obligation may vary by size and sector and considered that States should establish “differentiated” obligations based on companies’ current and historic contribution to climate change, imposing stricter duties on companies that engage in higher-carbon sectors (in accordance with the “polluter pays” principle). 

As examples of the types of obligations States could impose, the Court specifically referred to restrictions on business operating conditions, tax burdens, transition plans and strategies, investment in education, adaptation measures, and addressing loss and damage.

What’s next?

While this Opinion is not binding, the Court makes clear that it must be considered in a comprehensive manner by State that are Parties to the ACHR and all those that make up the Organization of the American States. 

It is also likely that this Opinion (along with the ITLOS and ICJ opinions referred to above) will be used as building blocks for future climate litigation, continuing the increasing use of human rights arguments to further climate-related objectives.  

For more detail on recent climate trends, see our blog post on the 2025 report by the Grantham Institute on Climate Change and the Environment.