25 July 2025
State obligations under international law and their consequences in the context of climate change
On Wednesday 23 July 2025, the International Court of Justice issued its long-awaited advisory opinion on the obligations of States under international law in the context of climate change.
In the groundbreaking opinion, the Court clearly establishes that States have legally binding obligations to protect the climate system, including in order to uphold their human rights obligations, and can be held accountable for their failure to do so.
The opinion marks a major victory for climate activists and human rights defenders around the world, and in particular the Pacific Islander students who drove the initiative for an ICJ opinion from the beginning. It shows what can be done when States and human rights defenders work together on a common cause.
Finding the protection of the human right to a clean, healthy and sustainable environment to be a precondition for the enjoyment of human rights, and considering the impact of climate change on the rights to life, health and an adequate standard of living, among other human rights, the Court held that States have obligations under international human rights law to combat climate change.
This may include obligations to adopt standards and legislation, and to regulate private companies.
These obligations interconnect with equally strict duties flowing from other relevant international law, as outlined by the Court, including climate change treaties such as the Paris Agreement, and customary international law.
The opinion complements the recent advisory opinion of the Inter-American Court of Human Rights and marks a significant step forward for climate justice that must now lead to a radical change in approach from States.
I will be examining the opinion further in the build up to my upcoming report on human rights defenders, climate change and a just transition, which I will present at the 80th session of the UN General Assembly this October.