
Increasingly, courts are stepping in where climate diplomacy stalls. The year 2025 marks a turning point, with landmark legal developments such as the Advisory Opinion of the International Court of Justice (ICJ), the Advisory Opinion of the Inter-American Court of Human Rights, and the Lliuya v. RWE ruling. These cases are highly relevant for COP30 and the broader UNFCCC process: they clarify legal responsibilities for climate action and harm, turning moral imperatives into tangible legal duties.
Our policy brief explores the key results of 2025 litigation milestones and analyses how these developments can inform and accelerate negotiations under the UNFCCC, with a particular focus on NDC ambition and the new global climate finance goal, as well as loss and damage (finance).