Climate Justice Is No Longer An Aspiration But A Legal Duty

In recent months, both the Inter-American Court of Human Rights (IACHR) and the International Court of Justice (ICJ) issued advisory opinions that constitute unprecedented legal milestones for global climate justice. They called on states to act urgently to guarantee the right to a healthy environment, including a healthy climate, to prevent significant damage to the climate, and to provide comprehensive reparations for damage already caused, when applicable.

Both decisions were the result of unprecedented legal and civil society participation that reflects the need to recognise the causes and consequences of the climate emergency, and to clarify the obligations of states in this regard, as well as those of private actors. In the process leading up to the IACHR’s advisory opinion, published on 3 July, hundreds of Indigenous peoples, local communities, civil society organisations and human rights defenders participated through public hearings and written observations. For its part, the ICJ’s advisory opinion, issued on 23 July, was prompted by Vanuatu and supported by more than 130 countries.

Together, these opinions consolidate a more comprehensive international legal framework and open the door to the structural transformations that our societies and ecosystems demand. They recognise that climate change is “an existential problem of planetary proportions” that threatens “all forms of life” as well as the “effective enjoyment of all human rights”. Given the gravity of this situation, they confirm that states have legal obligations that include prevention, mitigation, adaptation and reparation for climate damage.

The courts affirmed that states must cooperate in the face of the climate emergency. The ICJ maintains that all states, including those that are not party to climate treaties, have an obligation to prevent significant damage to the climate under customary international law. For its part, the IACHR affirmed that states have a reinforced duty of due diligence to prevent foreseeable climate damage, even beyond their borders. It also delved into the need to adopt gender-sensitive, intersectional and participatory approaches in all climate policies, as well as to take specific measures in situations of particular vulnerability, such as those faced by children, Indigenous, tribal and Afro-descendant peoples, and peasant and fishing communities.

Without disregarding the richness and breadth of the contributions of both opinions, there are two fundamental aspects of these decisions that we wish to delve deeper into, elements which seek to guarantee the rights of those who are experiencing the most serious consequences of the climate crisis.

Reparation for damage caused by the climate crisis

Both courts made it clear that repairing climate damage is a specific, enforceable and multidimensional legal obligation. With slight nuances in their reasoning, they affirmed that states have a duty to repair the damage resulting from their failure to fulfil their climate obligations – by action or omission – with measures of ecological restitution, rehabilitation, compensation or redress, and guarantees of non-repetition that strengthen the resilience of territories.

One of the most significant contributions of the IACHR opinion is the recognition of comprehensive reparation as a fundamental pillar of climate action, alongside mitigation and adaptation. This is a response to the historical demands of the Global South in the face of a significant omission in the international climate regime: the exclusion of legal responsibility in Article 8 of the Paris Agreement, which has left millions of people affected by climate loss and damage without access to effective reparation.

Although the Loss and Damage Fund, put into motion during the 2023 UN Climate Change Conference (COP28), represents a political advance in the recognition of responsibilities for the impacts of climate change, it is clearly insufficient from the perspective of climate justice and international law. As the Inter-American Court of Human Rights pointed out in its opinion, this mechanism does not guarantee full reparation for the damage and losses attributable to states, does not ensure a fair distribution of the climate debt, nor does it replace the international obligations of reparation arising from their responsibility for actions or omissions that aggravate the climate crisis. Consequently, although the fund may serve as an instrument of immediate relief, it does not respond to the structural demands for reparation, accountability and justice that the climate crisis requires. The IACHR’s recognition opens the door to demands for its reform, direct legitimisation by affected communities and the adoption of rights-based criteria.

The Inter-American Court further stated that comprehensive reparation must address “the structural causes that aggravate the vulnerability of certain persons, peoples and ecosystems”. It also established that reparation cannot be limited to economic compensation and must be transformative, participatory, culturally relevant and designed based on the best available science and knowledge.

Participation, justice and protection for defenders

The ICJ opinion, meanwhile, recognised that treaties on access to information and public participation are relevant to addressing climate change. By emphasising the duty of cooperation, good faith in state action and special protection for the most vulnerable populations, its decision reinforces the need for states to establish transparent, accessible and inclusive decision-making processes as an indispensable condition for legitimate and effective climate action.

For its part, the IACHR takes up the standards of the Escazú Agreement – Latin America and the Caribbean’s regional treaty on environmental rights – devoting a substantial part of its opinion to developing the idea that access to environmental information, effective participation in climate decisions and access to environmental justice are essential conditions for guaranteeing human rights. It established that states must produce useful and accurate information, combat misinformation, allow meaningful participation (with a real capacity to influence the content and final outcome of decisions) from the earliest stages of a decision, and guarantee accessible, effective and adequate resources for those affected by the climate crisis. This includes adaptations for Indigenous peoples, children, persons with disabilities and other historically excluded communities, such as fishing communities.

In line with the above, the IACHR opinion recognised the high levels of violence faced by environmental defenders and reaffirmed the reinforced obligation to protect them, as well as to prevent, investigate and punish any form of persecution against them, taking into account the differentiated risks faced by certain groups. Furthermore, it advises that states must review regulatory frameworks that have been illegitimately used to criminalise those who carry out this important work for democracy and the rule of law.

Climate justice as an urgent legal duty

The legal and political power of both the ICJ and IACHR decisions is due in part to the fact that they come at a historic and critical moment for humanity. Social movements have at their disposal multiple international jurisdictions – including the 2024 decision of the International Tribunal for the Law of the Sea and the forthcoming opinion of the African Court on Human Rights – to build a new international climate law anchored in the protection of human rights and nature.

In the face of the climate emergency, these opinions constitute clear legal mandates that can help end climate impunity and demand the transformation of the structures that perpetuate harm.

The standards developed by both courts must now be rooted in territories, strengthening social mobilisation and guiding judicial decisions, legislative reforms and public policies. Because if they make one thing clear, it is that climate justice is no longer just an aspiration – it is an urgent legal duty.

(Published under Creative Commons from Dialogue Earth)