This never happened! Never have so many countries participated in an international legal proceeding before the highest judicial body of the United Nations. 96 countries, many of them for the first time, delivered their arguments before the International Court of Justice (ICJ) in the oral proceedings between 2 and 13 December 2024.1
A brief reminder of what is being asked and who asked it. This is not an adversarial case, one in which, for example, a Small Island Developing State (SIDS) is “suing” a developed country for its allegedly unlawful activities under international law that have led, and are continuing to lead, to dangerous climate change. This is not what these proceedings are about, but keep that scenario in mind. I will get back to it at the end of this short piece.
What we are witnessing is an Advisory Opinion proceeding. This happens when a body like the United Nations General Assembly requests the ICJ to answer a question of international law. In this case, the questions are two, and are very broad.2 The first is to clarify what are the State obligations to protect the climate system. The second is to determine the legal consequences arising from State’s actions or omissions that lead to significant harm to the climate system. For both questions, the Court is asked to consider carefully the situation of vulnerable groups and States as well as future generations. SIDS are explicitly included in the questions posed to the Court.
The question does not come out of the blue. It has been the result of years of campaigning and of negotiation. It started in the classrooms of the University of the South Pacific, continued as a vociferous youth campaign and ended with inter-governmental negotiations before the UNGA.3 Vanuatu has been seen as leading the charge in relation to the UNGA request and ensuing Advisory Opinion proceedings, but the truth is that there is a core group of States – not all SIDS – who backed the request and contributed to the formulation of the question posed to the Court.4
A more in depth analysis of the oral proceedings (and written submissions) will highlight numerous legal and political issues. However, in my opinion the crux of the Advisory Opinion was clear in the diverging oral statements of the United Kingdom and St Lucia on Tuesday 10 December.5 You have a number of countries like the UK who argue that the answer to what States are obliged to do to protect the climate system lies exclusively in the Paris Agreement. There are others, like St Lucia, who argue that the Paris Agreement is one of many sources of international law that provides obligations on States to protect the climate system. In addition to other treaties, they argued strongly that customary international law imposes obligations on “all” States to protect the climate system.
Why are the two different answers important? and what does it change in practice and from a political point of view for SIDS? To put it simply, if state obligations to protect the climate system were limited to the ones found in the Paris Agreement, then they would apply only to the Parties to the Paris Agreement. Furthermore, legal consequences stemming from any breaches from Paris Agreement provisions would be regulated “only” by ad-hoc rules within the Agreement itself. States who may decide to leave the Paris Agreement would be free to not follow the Paris Agreement rules and no legal consequences would ensue from such decision.
If, on the other hand, state obligations to protect the climate system were to be found in customary international law, then they would apply to “all” States, whether they are parties or not to the Paris Agreement. Furthermore, the breach of a customary international law obligation leads to an internationally wrongful act. The latter leads to a number of legal consequences that should be imposed on the State acting unlawfully. These are the cessation and non-repetition of the unlawful action or omission, reparation and satisfaction.
How does this play out for SIDS? If the Court follows the UK approach, SIDS will be forced to “only” play the Paris Agreement game, one which they are obviously frustrated with and do not have much confidence in. If they feel that a developed country like the UK is breaching the Paris Agreement obligations, their options for redress within the Paris Agreement are limited. Even worse, if a country leaves the Paris Agreement, SIDS will have no redress against it.
If the Court follows St Lucia’s approach, things change considerably. SIDS would then still work their way around the Paris Agreement structure, but will also have the opportunity to challenge the UK’s alleged failure to abide by its customary international law obligations to protect the climate system. Should the Court take such an approach, which is not a given, then SIDS have to make a strategic decision. They can either use the threat of seeking redress in general international law against developed countries to boost and strengthen the Paris Agreement and climate change multilateralism. Or they can decide to seek their political objectives related to climate finance, mitigation, adaptation, loss and damage, sea level rise and self-determination mostly through international dispute settlement relying heavily on customary international law.
To conclude, SIDS have punched above their weight in taking the biggest problems of all times to the biggest Court of the world. SIDS have now to take a very important strategic decision that can have important consequences for climate change multilateralism. What is clear from their oral statements is that they will not go under (water) without a (legal) fight. I am under the impression that this will not be the last time we will see SIDS before the ICJ and other international courts.
References
- The “verbatims” (word by word account of the oral statements) are available at https://www.icj-cij.org/case/187.
- The questions before the ICJ can be found at https://www.vanuatuicj.com/resolution.
- The campaign has been spearheaded and led by the Pacific Islands Students Fighting Climate Change (PISFCC) – https://www.pisfcc.org/
- The diplomatic efforts led by Vanuatu to bring the question before the United Nations General Assembly and secure a resolution can be explored more in depth at https://www.vanuatuicj.com/
- The videos of the oral statements of the UK followed by St Lucia can be found at https://cdnapisec.kaltura.com/index.php/extwidget/preview/partner_id/2503451/uiconf_id/43914941/entry_id/1_ugsq2gzk/embed/dynamic
