Inter-American Court delivers historic Advisory Opinion on Climate Change

21/07/25

On 3 July 2025, the Inter-American Court of Human Rights (“the Court”) handed down Advisory Opinion OC‑32/23, providing guidance on the nature and scope of states’ international law obligations in the context of the climate emergency. It is a novel and substantial (234 page) Opinion. The following findings are of particular note:

1. The Right to a Healthy Climate

For the first time, the Court recognised the right to a healthy climate as a human right grounded in (and complementary to) the right to a healthy environment. The right is conceptualised as having both individual and collective dimensions and protecting human populations, ecosystems and future generations (paras [298]–[304]).

2. Recognition of the Rights of Nature

The Court held that nature is the subject of legal rights, and that States have corresponding obligations to protect, restore, and regenerate ecosystems (para [283]). The Court’s recognition of ecosystems as subjects of protection reflects the jurisprudence and domestic laws of various States subject to the Court’s jurisdiction, including Ecuador, whose constitution explicitly recognises nature (Pachamama) as a rights holder.

3. Jus Cogens Nature of the Obligation not to Cause Irreversible Damage to the Climate and the Environment

The Court affirmed that the obligation to prevent irreversible damage to the climate qualifies as a jus cogens, or peremptory, norm of international law (para [287]–[294]). This controversial and novel finding is grounded in: (i) the principle of effectiveness, as the duty to preserve the “common ecosystem” was held to be a sine qua non for the enjoyment of all other fundamental rights recognised by the Court (para [290]); (ii) the “universality of the underlying values” of preservation which affect “the existential interests of all individuals and species of all kind” (para [291]); and (iii) the progressive crystallisation of environmental obligations in international environmental law (para [287]).

2. Mitigation and Adaptation

The Court recognised that States have substantive duties to combat climate change through mitigation and adaptation measures. States are required to: (i) adopt regulatory frameworks setting quantifiable GHG reduction targets; (ii) monitor and enforce those regulations; and (iii) adapt to climate impacts to protect vulnerable groups. The Court linked these duties to the protection of rights under Articles 4 (life), 5 (personal integrity), 8 (judicial protection), and 26 (progressive development) of the Convention (paras [323]–[363]).

6. Extraterritorial Application of Human Rights

The Court recognised that human rights obligations extend beyond national borders in the context of transboundary environmental harm. States may therefore be required to provide redress to persons or other States adversely affected by activities under their jurisdiction, even where the harm is felt extraterritorially (para [551]).

7. Protection for Climate-Displaced Persons

The Court recognised that climate change is both a direct and indirect cause of forced migration and affirmed that many cross-border movements are directly attributable to climate-related harms. The Court found that climate displacement may justify refugee or equivalent legal status and recognised a duty to cooperate to respond to displacement and collaborate on migration governance, including by offering protection pathways (e.g., temporary visas) for displaced persons (paras [433]).

The Court’s Opinion is one of four requests put to international tribunals regarding climate change. In May 2024, the International Tribunal for the Law of the Sea (“ITLOS”) handed down its Advisory Opinion on States’ obligations to address climate change under the United Nations Convention on the Law of the Sea (“UNCLOS”). Two further Advisory Opinions are pending before the International Court of Justice (“ICJ”) and the African Court on Human and Peoples’ Rights.

The Advisory Opinion is available here.