Litigating for the Planet: How International Courts and Tribunals Converge and Diverge on Climate Change

Authors

Paul R. Williams
Greta Ramelli
Ryan Jane Westlake

Abstract

As the global community faces mounting repercussions of climate change and a narrowing timeline to avert irreversible environmental harm, the role of international law in climate change litigation has become increasingly critical. In recent years, hundreds of climate change cases have been filed against governments and corporations before domestic courts. The year 2023 marked an unprecedented rise in the engagement of international and regional courts with climate issues. Notably, the European Court of Human Rights and the International Tribunal of the Law of the Sea recently expressed their views on the scope of state obligations concerning climate change under the European Convention on Human Rights and the United Nations Convention on the Law of the Sea. The InterAmerican Court of Human Rights and the International Court of Justice are also set to deliver their advisory opinions on state obligations under applicable human rights and international law frameworks to prevent environmental harm arising from climate change and protect vulnerable ecosystems and populations.

The rapid and unprecedented developments in the international law space warrant the question of whether the judgments and advisory opinions issued and set to be issued by international courts and tribunals will consolidate or fragment climate change litigation. This article contends that, though the legal questions brought before international courts and tribunals are different in points of law and, consequently, the approach of courts and tribunals varies, the recent developments in the climate change litigation space are greatly contributing to a better understanding of state obligations under human rights law and international law to take effective measures to protect the environment from climate change.

The plurality of approaches of international courts and tribunals highlights the complexity of climate change issues—spanning human rights, environmental law, economics, and international relations—and underscores the capacity of the international legal system to address the multifaceted nature of climate change across different legal frameworks. Rather than exposing a weakness, this plurality demonstrates the adaptability and resilience of international law in addressing climate change from different angles. This article examines how various international courts and tribunals have responded to climate litigation thus far and considers their potential impact on the fragmentation or consolidation of climate change litigation.

Recommended Citation

Paul R. Williams et al, Litigating for the Planet: How International Courts and Tribunals Converge and Diverge on Climate Change, 53 Denv. J. Int'l L. & Pol'y 333 (Spring 2025).