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ClientEarth Communications

11th September 2023

Climate litigation

The global legal initiatives you should be following in 2024

In December 2022, a coalition of small island states from across the world lodged a legal request to a tribunal in Hamburg, Germany. There was minimal fanfare.

But it’s possible this intervention will become a turning point in climate law and action.

So how could a tribunal focused on the law that governs the world’s ocean make a difference in the fight to curb the climate crisis?

Small island states – next-generation climate action

Climate impacts such as ocean warming, acidification and rising sea levels are already disastrous for small island nations. In early March 2023, Vanuatu faced two category four cyclones within 72 hours – unprecedented in history. Island inhabitants are bringing these impacts to the world’s attention: few can forget Tuvalu’s climate minister giving a pre-COP27 address knee-deep in the ocean.

Inhabitants are also taking these concerns to the world’s highest courts and tribunals. In one case last year Torres Strait Islanders won historic legal action against Australia for climate-induced damages to their ancestral lands.

The Commission of Small Island States on Climate Change and International Law (COSIS) is a collective of countries that are low-emitting, but highly vulnerable to the impacts of climate change and rising sea levels.

COSIS was formed in 2021 at the international climate talks in Glasgow and has taken action to define the obligations of states to protect the marine environment under international law. Its members include Antigua and Barbuda, Tuvalu, Palau, Niue, Vanuatu, Saint Lucia, Saint Vincent and the Grenadines, Saint Kitts and Nevis and the Bahamas.

In December 2022, COSIS lodged a ground-breaking legal request in Hamburg to the International Tribunal for the Law of the Sea (ITLOS), a near-globally applicable UN convention that establishes the legal order applicable to the world’s seas and ocean. This request is one of three current efforts that seek clarifications on the big legal questions about how states must deal with climate change under international law.

Climate questions – the open items in international courts

Climate change impacts all areas of life and law. For decades, small island states have championed international, co-operative efforts under the existing international treaty governing climate change and greenhouse gas reductions: the United Nations Framework Convention on Climate Change, and the Paris Agreement made under it.

Now, they are also assuming leading roles in clarifying international legal obligations to push along the global efforts to mitigate climate change.

On 29 March 2023, the United Nations General Assembly passed a resolution requesting an advisory opinion on climate change and human rights from the world’s highest court, the International Court of Justice (ICJ).

The initiative was kicked off by the Pacific Island Students Fighting Climate Change, championed by Vanuatu and supported by World’s Youth for Climate Justice. This means the ICJ will now be asked to clarify states’ obligations to limit climate harm to the human rights of present and future generations and the environment, and the consequences under international law if they fail to do so.

Meanwhile, in January 2023, Colombia and Chile submitted a request for an advisory opinion to the Inter-American Court of Human Rights to clarify what obligations states have when it comes to climate change under the human rights treaty signed by countries throughout the Americas. It's expected that this case will attract wider-ranging interest from states and non-governmental organisations, who also have the ability to file submissions. The deadline for written submissions on the questions before the court was 18 December 2023 and ClientEarth filed an amicus with the court.

And just as the Vanuatu resolution passed, the highest European human rights body, the European Court of Human Rights, started for the first time to examine similar questions brought by a group of Swiss senior women and a French citizen.

ClientEarth has filed a supportive intervention in the Swiss case, which raises novel and important questions of the interpretation of the legal duties of Switzerland to reduce its emissions to prevent harm to the elderly.

Meanwhile, COSIS’s request seeks the resolution of a legal question under the Law of the Sea. The convention secures the protection of the marine environment and requires all nations to reduce pollution that puts the health of the world’s oceans in jeopardy. The hearings concluded in late September 2023, just as the European Court of Human Rights heard its third climate case brought by a group of Portuguese youth.

All these could have major knock-on effects in terms of countries’ obligations around climate-harming emissions.

What does the Law of the Sea have to do with climate change?

Global warming is having significant negative impacts on the world’s seas – from ocean acidification to heating and sea level rise. Our ocean acts as the largest sink for carbon dioxide emitted from land-based sources, including industry and transportation. This excess CO2 raises the ocean’s temperatures, which has negative effects on marine life and ecosystems.

This is why COSIS is seeking answers on the obligations of countries under the Law of the Sea. Their question is whether state parties’ failure to limit greenhouse gas emissions, and the resulting negative effects on the marine environment, could be seen as a contravention of the Law of the Sea, and whether nations must take steps to reduce that harm.

A finding on this question would open up an essential area of law directly relevant to the climate crisis, but where obligations are still unclear – astonishing given that the world’s oceans cover over 70% of the Earth’s surface.

“States shall take, individually or jointly as appropriate, all measures consistent with this Convention that are necessary to prevent, reduce and control pollution of the marine environment from any source, using for this purpose the best practicable means at their disposal and in accordance with their capabilities, and they shall endeavour to harmonize their policies in this connection.” - Article 194(1), Law of the Sea Convention.

Law of the Sea advisory opinion – a turning point in international climate action?

The small island state commission has asked ITLOS for an advisory opinion. The first step is the submission of written statements by states parties and invited intergovernmental organisations. The deadline for this was 16 June 2023. 32 states, the European Union and nine intergovernmental organisations including COSIS, the African Union and the International Union for the Conservation of Nature filed submissions about what the above obligations mean in light of the climate crisis.

ClientEarth, as well as eight other civil society organisations and the UN Special Rapporteurs on Human Rights and Climate Change, Toxics and Human Rights and Human Rights and the Environment filed a submission to the Tribunal that does not form part of the official case file. ClientEarth’s submission is an updated version of our previously published legal briefing and can be accessed on the Tribunal’s website.

A positive advisory opinion could be essential to the global fight against climate change. A legal interpretation by the tribunal that the Law of the Sea requires states all over the world mitigate their greenhouse gas emissions to prevent harm to the marine environment opens up the possibility that climate commitments such as those made under the Paris Agreement may need to be enforced to protect the world’s oceans.

The advisory opinion is expected in 2024.

Are we about to see other climate law breakthroughs?

Domestic and international courts are increasingly being asked to define the exact content of state obligations to prevent climate change. And as the impacts become clearer and come to bear more heavily on the most vulnerable, we are likely to see courts increasingly taking this into account.

2024 is shaping up to be the year that international climate action takes some momentous steps forward.

Read ClientEarth’s legal briefing on the ITLOS advisory opinion.

Read ClientEarth’s amicus submission to the Inter-American Court of Human Rights.

If you would like to contact our lawyers, please see their contact details in the above briefing.