In recent years, national and international courts have been called upon to delineate States’ obligations in the face of the climate emergency. The expansion of climate litigation, promoted by non-governmental organisations, movements, and civil society groups, reflects not only the growing accountability of States for the inadequacy of their environmental policies but also a transformation in how States’ duties towards climate change are understood. The duty to mitigate and adapt to climate change is now interpreted not merely as an environmental obligation but as a legal duty linked to the protection of fundamental rights.

Viewing the climate crisis through the lens of human rights has produced a singular phenomenon: courts from diverse legal traditions and political contexts have developed distinct approaches to defining States’ duties to protect individuals and vulnerable groups from the impacts of climate change. While the European Court of Human Rights (ECtHR) grounds its analysis in individual protection, the Inter-American Court of Human Rights (IACtHR) expands it to collective dimensions, and the International Court of Justice (ICJ) seeks to articulate a universal legal language capable of bridging both.

In Verein KlimaSeniorinnen Schweiz and Others v. Switzerland (9 April 2024), the ECtHR held that climate change constitutes “a serious current and future threat to the enjoyment of human rights guaranteed under the Convention” (para. 436). Relying on Article 8 of the Convention, concerning the right to respect for private and family life, the Court recognized that States have a duty to ensure “effective protection from serious adverse effects of climate change on individuals’ life, health, well-being and quality of life” (para. 519), thereby imposing positive obligations of mitigation and adaptation (para. 545). This decision marks a turning point: mitigating the effects of climate change is no longer a matter of political discretion but an integral component of the European human rights framework, albeit within the States’ margin of appreciation.

The IACtHR, in its Advisory Opinion No. 32/25 (The Climate Emergency and Human Rights, 29 May 2025), adopts a different conceptual matrix. It advances a relational and community-based understanding of human rights, recognising that climate change affects not only individuals but also communities, Indigenous peoples, and historically marginalised groups. The Court asserts States’ obligations to adopt all necessary measures to reduce both climate-related risks and the vulnerability of affected populations (para. 227), acknowledging the differentiated vulnerability of Indigenous peoples, women, and local communities. It further distinguishes between “substantive rights” (life, personal integrity, health, property) and “procedural rights” (freedom of expression and association, access to information, participation, and effective remedies), stressing that respect for the latter “is an essential requirement to ensure the legitimacy and effectiveness of climate action” (para. 458).

The ICJ, in its Advisory Opinion of 23 July 2025 on Obligations of States in respect of Climate Change, seeks to translate these experiences into a universal legal vocabulary. It declares that “the protection of the environment is a precondition for the enjoyment of human rights” (para. 373), recognizing that global warming impacts, such as sea-level rise, desertification, and natural disasters, “may significantly impair the enjoyment of certain human rights” (para. 376), including the rights to life, health, an adequate standard of living, and the rights of women, children, and Indigenous peoples (paras. 377-382). By articulating a “common grammar” that interlinks climate and human rights obligations, the ICJ plays a synthesising role, seeking a shared minimum standard that integrates diverse legal traditions without erasing regional specificities.

These rulings represent distinct yet converging attempts to address the same global challenge. Nevertheless, while recognising the interdependence between climate and human rights, they may also lead to fragmentation and uncertainty concerning the coherence of legal regimes. Such fragmentation stems not only from interpretative divergences but also from the absence of institutional mechanisms fostering a coherent judicial dialogue.

The extension of human rights discourse to the climate sphere marks a significant step forward in ensuring the effectiveness of States’ obligations. Yet, it also poses the challenge of harmonising multiple jurisdictions and normative orders, avoiding the transformation of pluralism into fragmentation. The transformative potential of this development depends on a structured inter-institutional dialogue, acknowledging that the protection of human rights and the environment is not the monopoly of any single legal order.

 

(Focus by Bernardo Mageste Castelar Campos)

 

Selected bibliography:

 

H. Arling, H. Taghavi, KlimaSeniorinnen v. Switzerland – A New Era for Climate Change Protection or Proceeding with the Status Quo?, in EJIL: Talk!, 6 aprile 2023.

 

S. Atapattu, Climate Litigation, International Human Rights and the Right to a Healthy Environment: Connecting the Dots, in F. Sindico, K. McKenzie, G. Médici Colombo, L. Wegener (a cura di), Research Handbook on Climate Change Litigation, Cheltenham, 2024, 304 ss.

 

C.A. Gomes, H. Oliveira, A. Rocha, M. Fermeglia (a cura di), Climate Change Before International Courts: A Comparative Study, Londra, 2026.

 

R. Pisillo Mazzeschi, Diritti umani e cambiamento climatico: brevi note sulla sentenza KlimaSeniorinnen della Corte di Strasburgo, in Diritti umani e diritto internazionale, 2024, 383 ss.

 

S.A. Samuel, J.A. Carrillo Bañuelos, The Role of Advisory Opinions in International Law in the Context of the Climate Crisis: The Dialogue between the ICJ, the ITLOS, the IACtHR, and the AfCtHPR, in M.A. Tigre, A. Rocha (a cura di), The Role of Advisory Opinions in International Law in the Context of the Climate Crisis, Leiden, 2025, 116 ss.

 

F. Sindico, M. M. Mbengue (a cura di), Comparative Climate Change Litigation: Beyond the Usual Suspects, Cham, 2021.

 

Cited case law:

 

Verein KlimaSeniorinnen Schweiz e altri c. Svizzera, n. 53600/20, Corte EDU (Grande Camera), 9 aprile 2024.

L’emergenza climatica e i diritti umani, Parere Consultivo n. 32/25, Corte IDU, 29 maggio 2025.

Obblighi degli Stati rispetto al cambiamento climatico, Parere consultivo, Corte internazionale di giustizia, 23 luglio 2025.

 

Related case law:

 

Carême c. Francia, n. 7189/21, Corte EDU (Grande Camera), 9 aprile 2024.

 

Duarte Agostinho e altri c. Portogallo e 32 altri, n. 39371/20, Corte EDU (Grande Camera), 9 aprile 2024.

 

Ambiente e diritti umani, Parere Consultivo n. 23/17, Corte IDU, 15 novembre 2017.