Climate change poses a dire threat to all life forms, and slow-moving countries have been issued a warning in a groundbreaking court decision.
The International Court of Justice (ICJ) has delivered a historic ruling on climate change, setting a new baseline for global action against this pressing issue. The advisory opinion, issued in 2025, establishes that high-emitting countries have clear international legal obligations under both environmental and human rights law to reduce their greenhouse gas emissions and protect the climate system.
The ruling, while non-binding, is authoritative and widely expected to influence future international climate governance, dispute resolution, and state behaviour. It reinforces legal accountability for emissions and climate-related harm under international law.
High-emitting countries must take proactive steps to reduce greenhouse gas emissions, consistent with treaties like the Paris Agreement and other environmental conventions they have ratified. They must act with due diligence in environmental protection and cooperate with each other to address climate change, reflecting both environmental and human rights treaty commitments.
The Court reinforced that a clean, healthy, and sustainable environment is fundamental for enjoying many human rights, including the right to life and to health. High emitters have duties under international human rights law to effectively protect these rights by tackling climate change.
If States breach these duties, they bear international legal responsibility, which can entail stopping harmful activities, guaranteeing no repetition, and providing reparations (including financial support or other remedies) depending on circumstances.
The opinion also highlights State duties to prevent and remedy loss and damage caused by climate change impacts, which has particular relevance for developing countries affected disproportionately and requiring significant finance and support from wealthier emitters.
Even in cases where populations are displaced due to climate change impacts like sea-level rise, the obligations of States persist, including protecting displaced persons’ human rights and upholding territorial sovereignty as it relates to climate-induced displacement.
The ruling provides a measure of climate justice for small island states, and offers more legal options for small, climate-vulnerable nations like those in the Alliance of Small Island States in their efforts to encourage high-emitting nations to address climate change.
Notably, the ICJ ruling means that nations can be held legally liable for climate harms, even if damage stems from multiple causes, including the activities of private actors such as companies. It is scientifically possible to determine each nation's total contribution to global emissions, taking into account both historical and current emissions. Nations cannot seek an exemption because others have contributed to the problem.
The ruling also means that parties to global human rights agreements, such as the International Covenant on Civil and Political Rights, must take measures to protect the climate system and other parts of the environment. The full enjoyment of human rights cannot be ensured without the protection of the climate system and other parts of the environment.
The ICJ's ruling emphasizes the importance of international cooperation in addressing climate change and the need for all nations to take action, regardless of whether they are part of specific climate agreements or not. This ruling provides a significant step forward in the global fight against climate change, setting a clear path for international cooperation and accountability.
[1] International Court of Justice. (2025). Advisory Opinion on Climate Change. Retrieved from https://www.icj-cij.org/files/case-related/185/185-20250729-ADV-01-00-EN.pdf [2] United Nations Framework Convention on Climate Change. (2025). Loss and Damage. Retrieved from https://unfccc.int/process-and-meetings/the-convention/items/10444.php [3] United Nations Human Rights. (2025). Human Rights and Climate Change. Retrieved from https://www.ohchr.org/EN/Issues/ClimateChange/Pages/HRClimateChangeIndex.aspx [4] United Nations Development Programme. (2025). Human Rights and Climate Change. Retrieved from https://www.undp.org/content/undp/en/home/ourwork/environment-and-energy/climate-change/human-rights-and-climate-change.html
- The ICJ's 2025 ruling on climate change established high-emitting countries' international legal obligations to reduce carbon emissions, aligning with treaties like the Paris Agreement and other environmental conventions.
- The advisory opinion reinforces that high carbon emissions and climate-related harm are subject to legal accountability under international law, necessitating proactive climate change action.
- Science points to a connection between a clean, healthy, and sustainable environment and numerous human rights, including the right to life and health, contingent upon high emitting countries' efforts to combat climate change.
- Failure by high emitters to fulfill their international human rights duties in addressing climate change results in their bearing international legal responsibility for compensation, including financial support or other remedies.
- The ICJ ruling further indicates that parties to global human rights agreements must address climate change to protect the climate system and other environmental aspects for the sake of upholding the full enjoyment of human rights.
