Climate Change Litigation: Which Human Rights Meet the Bar?



The advisory jurisdiction of the International Court of Justice (ICJ) allows for the ICJ to give authoritative, guidance on legal questions arising from the functions of organs and specialised agencies. These opinions are non-binding but nevertheless often have significant legal and political effect. In March 2023, the UN General Assembly asked the Court for such guidance on states’ legal obligations and responsibilities in relation to climate change, including those arising under human rights law. The ICJ advisory opinion process is underway, with submissions due by states in January 2024.

In rendering its opinion, the Court must apply applicable sources of law. What can the Court do, if anything, with the large and growing body of climate litigation, in particular, human rights-based climate litigation? There are cases in international fora, such as the three Views of the UN human rights treaty bodies; regional fora, such as the requested advisory opinion in the Inter-American Court of Human Rights on climate change and human rights, and the currently three pending cases in the European Court of Human Rights; and in domestic courts around the world.

The best case for reliance on climate litigation is on decisions in individual cases by the UN human rights treaty bodies, even though these so-called ‘views’ do not strictly bind the parties (state parties that are subject to each treaty body have a good faith obligation to implement Views). In part, this is because the advisory opinion request specifically points to various international human rights law treaties. The ICJ can use the jurisprudence developed by the treaty bodies pursuant to article 38(1)(d) of the Statute of the ICJ, relying on the cases as a subsidiary means for the determination of international law. According to the ICJ’s ruling in Diallo, the treaty body cases should be given “great weight” to “achieve the necessary clarity and the essential consistency of international law”. This is in addition to the Court relying on the jurisprudence of the treaty bodies as ‘subsequent practice’ for the purposes of treaty interpretation pursuant to article 38(1)(a) of the ICJ Statute. 

There are three relevant treaty body cases, all decided in the last few years: Teitiota v New Zealand, Sacchi v Argentina and Billy v Australia. In Teitiota, the Human Rights Committee applied its General Comment No 36 to say that the right to life may be breached by reasonably foreseeable life-threatening environmental degradation, even if the threat does not result in the loss of life. However, the Committee held that New Zealand had not violated Mr Teitiota’s right to life by declining his so-called climate refugee claim because its decision to return him to Kiribati was not arbitrary nor in error. In Sacchi, the Committee on the Rights of the Child found that the respondent states’ impairment of the child authors’ rights to life, health and culture as a result of states’ acts or omissions regarding carbon emissions originating in their territory was reasonably foreseeable, and that the authors were ‘victims’ for the purposes of jurisdiction. But, as the authors had not exhausted domestic remedies, their claims were inadmissible. Billy, better known as the Torres Strait Islander case, is the first case where authors have succeeded on the merits. While the Human Rights Committee did not find a violation of the indigenous authors’ right to life, Australia had breached their rights to culture and to private, home and family life by its failure to implement a climate adaptation programme to ensure the long-term habitability of the low-lying islands.

The premise of the request for an advisory opinion is that climate law treaties alone do not determine states’ international law obligations in respect of climate change; human rights treaties do too. That is certainly borne out in the treaty body cases, particularly in respect of their findings on extraterritorial jurisdiction of the Convention on the Rights of the Child, the interpretation of the right to life in a climate context, and the applicability of the right to culture. Whether the ICJ adopts these cases and principles remains to be seen, but it has a solid legal foundation to do so.  

Biography entry

Rebecca is a prae doc university assistant and lecturer at the Institute of European, Comparative and International Law at the University of Vienna. Her PhD analyses human rights-based climate litigation in the context of international law. She has presented her work this year at the University of Cambridge, European University Institute, Universität der Bundeswehr München and, most recently, at the inaugural Ars Iuris conference at the University of Vienna. Prior to joining the University of Vienna, Rebecca practiced constitutional and human rights law as an Assistant Crown Counsel in New Zealand, taught legal research and writing at Victoria University of Wellington, and clerked at the New Zealand Supreme Court for the Hon Justice Susan Glazebrook. She has an LLB(Hons) and BA majoring in international relations from Victoria University of Wellington (New Zealand). Rebecca has also studied at Konstanz University (Germany) and Ludwig Maximillian University, Munich (Germany). She has worked as a research assistant for Professor Michael Waibel (Vienna), Professor August Reinisch (Vienna) for some of his International Law Commission work, Professor Campbell McLachlan KC (Wellington, NZ) and at the New Zealand Law Commission.