The Hague: In a historic ruling, the International Court of Justice (ICJ), the principal judicial organ of the United Nations, delivered a unanimous Advisory Opinion on the obligations of States concerning climate change, marking only the fifth unanimous decision in its nearly 80-year history.
The opinion, requested by the UN General Assembly through resolution 77/276 on March 29, 2023, addresses the legal responsibilities of States to protect the climate system and environment from anthropogenic greenhouse gas emissions, as well as the consequences for failing to meet these obligations. This landmark decision, described as a clarion call for global action, sets a robust legal framework that could reshape how nations address the escalating climate crisis, with profound implications for vulnerable States, present and future generations, and the international community at large.
The ICJ’s Advisory Opinion responds to two critical questions posed by the General Assembly. The first question seeks to clarify the obligations of States under international law to protect the climate system and other environmental components from human-induced greenhouse gas emissions. The second question examines the legal implications for States that cause significant harm to the climate system through their actions or inaction, particularly for small island developing States and other vulnerable nations, as well as for the peoples and individuals affected by the adverse effects of climate change. While not legally binding, the opinion carries significant moral and legal weight, offering authoritative guidance on how international law applies to the global climate crisis. It is expected to influence national policies, international negotiations, and potential future litigation, particularly for nations disproportionately impacted by rising sea levels, extreme weather, and environmental degradation.
The Court’s response to the first question outlines a comprehensive set of obligations rooted in multiple sources of international law. States parties to the United Nations Framework Convention on Climate Change (UNFCCC) are bound to adopt measures to mitigate greenhouse gas emissions and adapt to climate change. Those listed in Annexe I of the UNFCCC, primarily developed nations, bear additional responsibilities to lead in reducing emissions and enhancing carbon sinks. The Kyoto Protocol and Paris Agreement further impose specific duties, including the preparation and implementation of progressive nationally determined contributions (NDCs) aimed at limiting global warming to 1.5°C above pre-industrial levels. States must act with due diligence, cooperate in good faith, and pursue adaptation measures, supported by technology and financial transfers. Beyond treaty obligations, customary international law imposes a duty on all States to prevent significant environmental harm through diligent action and to cooperate continuously to safeguard the climate system. Additional treaties, such as the United Nations Convention on the Law of the Sea, the Vienna Convention for the Protection of the Ozone Layer, and human rights law, reinforce these obligations by requiring measures to protect marine environments and ensure the enjoyment of human rights impacted by climate change.
Addressing the second question, the ICJ clarified that any breach of these obligations constitutes an internationally wrongful act, triggering State responsibility. Such breaches may stem from actions like fossil fuel production, consumption, or subsidies, as well as failures to regulate private actors adequately. Responsible States face a continuing duty to cease wrongful acts, provide assurances against repetition, and offer full reparation to injured States through restitution, compensation, or satisfaction, provided a direct causal link between the act and harm can be established. The Court emphasised that while greenhouse gas emissions are cumulative and involve multiple States, scientific advancements allow for the attribution of each State’s contribution to global emissions, enabling accountability. Notably, the obligations to protect the climate system are deemed erga omnes, meaning all States have a legal interest in their fulfilment, particularly under the UNFCCC and Paris Agreement, which protect the global atmospheric commons.
The proceedings saw unprecedented global engagement, with 91 written statements and 62 written comments submitted by States and international organisations, followed by oral statements from 96 States and 11 organisations during public hearings from December 2 to 13, 2024. This record participation underscores the urgency and universal relevance of the climate crisis.
The Court’s reasoning began by affirming its jurisdiction to issue the opinion and rejecting any grounds to decline the request. It interpreted the General Assembly’s questions as encompassing the entirety of international law, not limited to specific treaties, and clarified that it was not tasked with assigning responsibility to individual States but with outlining a general legal framework. The Court also addressed challenges raised during proceedings, such as the cumulative nature of climate harm and difficulties in establishing causation. It noted that while causation in climate change cases is complex, a sufficiently direct and certain causal nexus can be established through scientific evidence and case-by-case assessments.
For Small Island Developing States and other vulnerable nations, the opinion affirms their equal entitlement to remedies under international law, despite their unique challenges due to geography and development levels. The Court also acknowledged the interests of present and future generations, though it clarified that their ability to invoke State responsibility depends on specific legal obligations. The opinion integrates guiding principles such as sustainable development, equity, and the precautionary approach, which inform the interpretation of these obligations. By rejecting arguments that climate treaties alone govern State responsibilities, the Court underscored the applicability of broader international law, ensuring a holistic approach to addressing climate change.
The Advisory Opinion concludes with a reflection on its role in guiding global action. The Court expressed hope that its findings would inform social and political efforts to combat the climate crisis, aligning with the UN’s mission to foster collective solutions. Several judges appended separate opinions and declarations, offering additional perspectives on the ruling’s implications. The full text and summary of the Advisory Opinion, along with these judicial contributions, are available on the ICJ’s website, providing a rich resource for policymakers, legal scholars, and activists.
This ruling arrives at a critical juncture as the world grapples with intensifying climate impacts. By articulating clear legal obligations and consequences, the ICJ has provided a blueprint for accountability that could empower vulnerable nations to seek redress and compel stronger global cooperation. As the international community navigates upcoming climate negotiations, this opinion is poised to serve as both a legal touchstone and a moral imperative, urging States to act decisively to protect the planet for current and future generations.
– global bihari bureau
