The UN General Assembly recently asked the International Court of Justice to issue an advisory opinion on the obligations of states with respect to climate change. This historic resolution, led by Vanuatu, one of several Pacific Island states endangered by climate change-induced sea-level rises, was the result of an energetic global campaign spearheaded by Pacific Island young people. Civil society continues to advocate for states to submit strong written statements to the court in the hope of obtaining a ground-breaking advisory opinion that could positively influence climate negotiations, encourage states to make more ambitious pledges and pave the way for further climate litigation victories.

As a matter of global justice, the climate crisis has rightfully made its way to the world’s highest court.

On 29 March 2023, the United Nations General Assembly (UNGA) unanimously adopted a resolution asking the International Court of Justice (ICJ) to issue an advisory opinion on the obligations of states on climate change. The initiative was led by the Pacific Island state of Vanuatu, co-sponsored by 132 states and actively supported by networks of grassroots youth groups from the Pacific and around the world.

This victory for the global climate movement comes a decade or so after the failure of similar attempts by Pacific Island states in the face of staunch opposition from major greenhouse gas emitters. But this time around, the science is clearer than ever and the climate movement has succeeded in pushing the crisis up on the agenda. Climate campaigners are starting to win legal victories against governments and corporations in courts around the world – efforts that could be strengthened with an ICJ opinion. The time was ripe.

The questions posed to the ICJ

Having particular regard to the Charter of the United Nations, the International Covenant on Civil and Political Rights, the International Covenant on Economic, Social and Cultural Rights, the United Nations Framework Convention on Climate Change, the Paris Agreement, the United Nations Convention on the Law of the Sea, the duty of due diligence, the rights recognized in the Universal Declaration of Human Rights, the principle of prevention of significant harm to the environment and the duty to protect and preserve the marine environment,

(a) What are the obligations of States under international law to ensure the protection of the climate system and other parts of the environment from anthropogenic emissions of greenhouse gases for States and for present and future generations;

(b) What are the legal consequences under these obligations for States where they, by their acts and omissions, have caused significant harm to the climate system and other parts of the environment, with respect to:

(i) States, including, in particular, small island developing States, which due to their geographical circumstances and level of development, are injured or specially affected by or are particularly vulnerable to the adverse effects of climate change?

(ii) Peoples and individuals of the present and future generations affected by the adverse effects of climate change?


See the full UNGA resolution, A/RES/77/276, here.

Civil society’s campaign

This campaign comes from and is led by people from Pacific Islands – countries suffering extreme impacts from climate change, with many islands at risk of disappearing under rising sea levels.

In 2019, a group of law students from the University of the South Pacific formed Pacific Islands Students Fighting Climate Change (PISFCC), a regional organisation with national chapters in Fiji, the Solomon Islands, Tonga and Vanuatu. Their aim was to seek an ICJ opinion, and to use this to develop international law on legal obligations towards environmental treaties and human rights. PISFCC also seeks to raise awareness among young people. It soon had members in every Pacific Island state.

PISFCC started by advocating with the Pacific Island Forum – the key regional body – to put the call for an ICJ opinion on its agenda. The government of Vanuatu announced it would seek this in September 2021, and Pacific civil society organisations (CSOs) expressed their support and willingness to campaign, forming an alliance – the Alliance for a Climate Justice Advisory Opinion – that has grown to include CSOs and many others from around the world, including UN Special Rapporteurs and global experts.

The UNGA resolution calling for an ICJ advisory opinion is the beginning of a wave of change in how we all think about the climate crisis and a reminder that climate change doesn’t respect geopolitical boundaries.


The campaign has made heavy use of social media, with people sharing their stories on the impacts of climate change and emphasising the importance of an ICJ opinion to help support calls for climate action, including climate litigation. It also produced a song for the movement, shared in the run-up to the UNGA decision.

The campaign organised globally, sharing a toolkit used by activists around the world, and took to the streets locally. In Vanuatu, where it all started, children demonstrated in September 2022 to call attention to the impacts of climate change as their country’s single greatest development threat and express support for the call for an ICJ opinion.

In the run-up to the UNGA session that adopted the historic resolution, thousands of CSOs from around the world supported a letter calling for governments to back the vote.

The ICJ’s role

Based in The Hague in the Netherlands, the ICJ is made up of 15 judges elected by the UNGA and UN Security Council. It settles legal disputes between states and provides advisory opinions on legal questions referred to it by other parts of the UN system.

The questions posed to the ICJ aim to clarify the obligations of states under international law to protect the climate system and environment from human-induced greenhouse gas emissions. They also ask about the legal responsibilities of states that have caused significant environmental harm towards other states, particularly small islands, and towards current and future generations.

To provide its advisory opinion, the ICJ will have to interpret states’ obligations as outlined in the 1992 UN Framework Convention on Climate Change and the 2015 Paris Agreement as well as the Universal Declaration of Human Rights and a variety of international covenants and treaties. It may consider previous UNGA resolutions on climate change, such as the recent one recognising access to a clean, healthy and sustainable environment as a universal human right, and other resolutions by the UN Human Rights Council and reports by the Office of the UN High Commissioner of Human Rights and its independent human rights experts. It may also take into account decisions by UN treaty bodies and its own jurisprudence on climate and environmental matters.

Voices from the frontline

Hailey Campbell is a climate activist and co-executive director of Care About Climate, a justice-driven climate education and empowerment CSO and network of international young climate leaders seeking to share climate solutions on the international stage.


The UNGA resolution calling for an ICJ advisory opinion is the beginning of a wave of change in how we all think about the climate crisis and a reminder that climate change doesn’t respect geopolitical boundaries. Environmental CSOs, young leaders, island nations leading the call for the resolution and PISFCC are reminding the world that before being an advocate, a fossil fuel executive, or a politician, we are all people. As humans, we all share this beautiful planet and sharing it requires caring about each other. If some leaders fail to recognise this, they should be held accountable.

The resolution is also a celebration of island innovation and perseverance.

But it is only the first step. Before the ICJ can issue its opinion, written and oral arguments from states and select international organisations, such as the UN Environment Programme, will be requested. It is important for community members to continue contacting their national representatives and international organisations selected to submit testimonies and call for support of the opinion. The PISFCC have just launched an amazing handbook to support policymakers, youth, and environmental CSOs in understanding their role that I highly recommend checking out. My favourite example from the handbook is about the importance of sharing your personal testimony as to why you believe in the need for an ICJ opinion on climate rights and what impact it could have on your future with your national representatives. I hope everyone feels empowered to join me in the Alliance to stay up to date on ways to make an impact.


This is an edited extract from our conversation with Hailey. Read the full interview here.

Next steps

According to its statute, the ICJ can seek written statements from states or international organisations likely to have relevant information on the issue at hand. On 20 April, the ICJ communicated its decision to treat the UN and all its member states as ‘likely to be able to furnish information on the questions submitted to the Court’ and gave them six months to submit written statements, after which they will have three months to make written comments on statements made by other states or organisations.

Civil society doesn’t have any right to submit formal statements, although for almost two decades the ICJ has allowed it to play a role by treating informal civil society submissions as readily available publications that may be referred to. Because civil society doesn’t have an institutional role to play, climate activists are urging as many people as possible to advocate towards their governments to make strong submissions that will lead to a progressive ICJ opinion.

After submissions close, the ICJ is likely to take several months to deliberate, so its opinion may be expected at some point in 2024, likely towards the end of the year.

Advisory opinions aren’t binding. They don’t impose obligations on states. But they shape the global understanding of states’ obligations under international law and can motivate states to show their compliance with rising standards.

By clarifying the obligations of states, an ICJ opinion could positively influence climate negotiations, pushing forward long-delayed initiatives on funding for loss and damage. It could encourage states to make more ambitious pledges to cut greenhouse gas emissions. It might also help raise awareness of the particular risks faced by small island states and provide arguments in favour of stronger climate action, helping climate advocates gain ground within governments.

A progressive advisory opinion could also help support domestic climate litigation: research shows that domestic courts are increasingly inclined to cite ICJ opinions and other sources of international law, including when it comes to determining climate issues.

The risk can’t be ruled out of a disappointing ICJ opinion merely reiterating the content of existing climate treaties without making any progress on states’ obligations. But climate activists find reasons to expect much more: many see this as a unique opportunity, brought about by their own persistent efforts, to advance climate justice and push for action that meets the scale of the crisis.


  • Civil society should keep up its networked campaign to encourage the submission of strong written statements to the International Court of Justice.
  • States that present themselves as climate champions should publicly express support for more demanding climate obligations under international law.
  • National-level courts should domesticate International Court of Justice opinions and other sources of international human rights law.

Cover photo by Save the Children Vanuatu/Facebook