Asociación Civil por la Justicia Ambiental v. Province of Entre Ríos, et al. (Delta del Paraná case)

In late Fall 2020, the uncontrolled burning of pastures in Ramsar’s wetland ecosystem (Delta del Paraná) created a serious environmental conflict between different provinces of Argentina. This conflict gave place to several lawsuits seeking protection for the ecosystem, including injunctions and damages for environmental and health consequences of the fires. One of these claims introduced climate concerns.

On July 03, 2020, two NGOs and a group of children represented by their parents filed a constitutional collective claim (amparo colectivo ambiental) against three Argentinean Provinces and a Municipality. The plaintiffs allege that the government entities are failing in their duties regarding the protection and sound environmental management of the inter-jurisdictional ecosystem, which is key for mitigation and adaptation of climate change while also being at risk due to its negative impacts. The complaint asks the Supreme Court to (i) declare the ecosystem as an entity subject to rights, (ii) order the defendants to prepare and implement a coordinated environmental management and land use plan that recognizes the vulnerability of the ecosystem and its relevance for future generations, (iii) designate a ‘guardian’ for the entity, responsible for monitoring its conservation and sustainable use, as well as informing the Supreme Court about the enforcement of the judgment, and (iv) order that broad, early and effective public participation is guaranteed in any decision-making regarding the future management of the ecosystem. The complaint relies primarily on the Argentinian constitution, the Convention on the Rights of the Child, the UNFCCC, the Paris Agreement, General Environmental Law No. 25.675 and Environmental Law to Control Burning Activities No. 23.919. The complaint also references laws in other countries recognizing the rights of nature, rivers, and other non-human entities.

On August 11, 2020, the Supreme Court made a first decision in one related case (Equística Defensa del Medio Ambiente v. Provincia de Santa Fe y ots). In the decision, the Supreme Court referred to Law 27.520 (Climate Change Adaptation and Mitigation Law) as a principal Law for the case and ordered the creation of an Environmental Emergency Committee and the submission of relevant information about the environmental problem and its management.

On December 28, 2021, the Supreme Court decided to combine all the related cases and informed that it will hand down a single judgment for all.

Finally, on December 4, 2025, the Supreme Court of Justice rendered a final judgment in the main proceedings, “Equística.” In that decision, it ordered the National State, the Provinces of Buenos Aires, Entre Ríos, and Santa Fe, and the municipalities of Rosario and Victoria to implement and execute the Comprehensive Strategic Plan for the Conservation and Sustainable Use of the Paraná Delta (PIECAS-DP), which had been established in September 2008. The Court ordered implementation of the measures agreed under the Plan, including equipment and infrastructure for early-warning mechanisms, the Network of Conservation Lighthouses (Red de Faros de Conservación), a systematic control plan, and a fire management plan for the Delta. The Court considered that its intervention had broken the status quo and facilitated the development of the basic regulatory and institutional tools necessary for the competent authorities to address the environmental problem. It nevertheless held that indefinite judicial monitoring of PIECAS-DP was not within the Court's role, as responsibility for its implementation lies with the relevant national, provincial and municipal political authorities. The final judgment made no reference to climate change and did not address the plaintiffs’ claims concerning climate change mitigation and adaptation.

Subsequently, on December 11, the Supreme Court replicated that ruling in the present case, “Asociación Civil por la Justicia Ambiental,” thereby declaring it concluded.