International Court of Justice says climate protection obligations are legally binding for States

On 23rd July, two years after the start of the proceedings, the International Court of Justice (ICJ) delivered its Advisory Opinion on the obligations of States to protect the climate system in respect of climate change.

Originally initiated by a group of law students in Vanuatu, which led to a remarkable diplomatic campaign, this process started in March 2023. The International Court of Justice (ICJ) was then requested by the UN General Assembly to shed light in these two questions:

1. What are the obligations of States under international law to ensure the protection of the climate system for present and future generations?

2 What are the legal consequences for States where they, by their acts and omissions, have caused significant harm to the climate system and other parts of the environment?

Obligations to protect present and future generations

In the Advisory Opinion, voted unanimously by its members, the Court makes it clear that climate protection duties are indeed binding for States. These obligations to protect present and future generations arise simultaneously from the UN Charter, the UN climate treaties, UNCLOS and other environmental treaties, human rights treaties, customary international law and general principles. The Court also characterizes these obligations as erga omnes, meaning States must comply with them since they owe them to the international “community as a whole”.

“This confirms that failure to comply—whether through inadequate national targets, fossil fuel licensing or lack of support for vulnerable States—can result in a range of full legal consequences under the law of State responsibility,” says Roberto Coll, international advocacy advisor at Rainforest Foundation Norway.

One possible consequence would be a so-called “cessation,” which implies the obligation to stop its actions that harm the climate and a duty to make full reparations.

“This is of paramount importance, since it gives Small Island States –like Vanuatu– and other climate vulnerable States full legal backing for the positions they have sought and fought for so many years”, says Coll.

The right to a clean, healthy and sustainable environment

When addressing human rights, the Court went even further and recognized the right to a clean, healthy and sustainable environment as a condition for the realization of other human rights. The ICJ has therefore joined the Inter-American Court of Human Rights in this notion.

It is expected that this Advisory Opinion will have implications for domestic courts and an effect in diplomatic processes, such as the upcoming COP 30, to be held in Belém (Brazil) in November.