IUCN to address the International Court of Justice in landmark climate change case on Friday

The International Union for Conservation of Nature (IUCN) will on Friday 13 December 2024 make history as it addresses the International Court of Justice (ICJ) in a groundbreaking process to determine the legal obligations of countries in respect to climate change and the consequences of failing to act.

These proceedings mark the first time the ICJ, the United Nations’ highest judicial authority, has taken up the issue of climate change, potentially reshaping global climate governance and strengthening the legal foundations for urgent action.

A total of 98  States and 12 international organizations have expressed their intention to participate in the oral proceedings before the Court. IUCN  will be represented by Dr Grethel Aguilar, IUCN Director General; Prof Christina Voigt, Chair of the IUCN World Commission on Environmental Law; and Prof Francesco Sindico, Co-chair of the Commission’s Climate Change Law Specialist Group.

IUCN’s legal team will respond to the two main questions the Court has been asked: What are the obligations of States under international law to ensure the protection of the climate system and other parts of the environment from anthropogenic emissions of greenhouse gases? And what are the legal consequences under these obligations for States where they have caused significant harm to the climate system and other parts of the environment?

“This is a pivotal moment in the fight against climate change,” said Dr. Grethel Aguilar, IUCN Director General. “The ICJ proceedings could establish that addressing climate change is not just a matter of political will or voluntary pledges—it is a binding legal responsibility. The opinion of the Court offers a powerful opportunity to hold nations accountable for safeguarding the planet, and our future generations.

“IUCN’s mission has always been rooted in conserving nature and supporting humanity to live in harmony with it,” said Dr Aguilar. “Through these proceedings, we aim to ensure that international law supports and enforces the urgent action needed to secure a liveable planet for all. The ICJ now has a unique and historical opportunity at a critical moment for our planet and people, to affirm that climate action is a legal imperative, not just a moral one.”

The proceedings follow a request by the UN General Assembly in 2023 for the ICJ to issue an advisory opinion on states’ legal duties to protect the global climate system.

IUCN requested and was granted the opportunity to participate. State and authorised organisations had until March 2024 to submit written submissions on the questions, and in August 2024 to offer written responses to other briefs filed. The proceedings have drawn unprecedented participation, receiving 91 written briefs and 62 follow-up comments from countries and international organizations.

Notably, IUCN stands out as the only organization representing both state and non-state members, underscoring its unique position as a bridge between governments and civil society.

“The sheer scale of engagement in this case reflects the urgency and importance of this issue,” said Prof Christina Voigt, Chair of the IUCN World Commission on Environmental Law.

“IUCN’s contributions draw on decades of scientific expertise and legal acumen to present a compelling argument for immediate and effective climate mitigation action, based on several international legal sources. Our voice represents the collective concerns of states, scientists, and communities around the world. The opinion from the ICJ could influence policies, investments, and lives worldwide.”

As the world faces intensifying climate impacts—from rising seas threatening small island nations to unprecedented heatwaves devastating communities—this process represents a critical moment in the global response to the climate crisis.

The ICJ proceedings, which began on 2 December, represent a turning point in international climate governance. The world will be watching as IUCN and other participants seek to chart a path toward stronger accountability, deeper cooperation, and a shared commitment to a sustainable future.

“The need to clarify state obligations to protect the climate system is more pressing now than ever, and we are honoured to have the opportunity to contribute to such a critical moment in history,” said Prof Francesco Sindico, Co-Chair of  WCEL´s Climate Change Law Specialist Group.

“As the oral proceedings are underway, IUCN and other participants will be looking to help chart the path for the future of our planet – so we can move forward with clarity.”

These proceedings are part of a broader global trend where courts are increasingly called upon to address climate inaction. In recent years environmental activists, impacted communities, and citizens have increasingly turned to national and international courts to enforce environmental laws and treaties. In April 2024, the European Court of Human Rights issued a landmark ruling that found that Switzerland had failed to fulfil its obligations under the European Convention on Human Rights related to climate change.

IUCN has also participated in the advisory proceedings before the Inter-American Court of Human Rights and the International Tribunal for Law of the Sea (ITLOS). ITLOS issued its advisory opinion on 21 May 2024 in which the Tribunal recognised that greenhouse gas emissions are a form of marine pollution and that states have specific legal obligations to address such pollution under the United Nations Convention on the Law of the Sea.