Symposium on the ICJ Climate Change Advisory Opinion: New Impetus for Climate Non-Refoulement Cases in International Court Advisory Opinions

[Monica Iyer is an Assistant Professor of law at the Georgia State University College of Law]

Climate change-related migration is an issue very much in the public mind, and the question of whether it is legal to send someone back (or refoule them) to a place where they might face human rights harms because of climate change has become a key question in climate and human rights litigation. In recent weeks, both the International Court of Justice (ICJ) and the Inter-American Court of Human Rights (IACtHR) issued advisory opinions on international legal responsibilities in the context of climate change, and both courts spoke to climate change-related migration and human rights. This brief article provides a refresher as to where things stand globally with regard to climate non-refoulement cases, presents the interventions made by the ICJ and IACtHR on this topic, and gives an initial analysis as to what the impacts of these Advisory Opinions might be in this area of climate change litigation. It suggests that while there is little new substance in the Advisory Opinions’ pronouncements on this area, the fact that the Courts have chosen to comment at all might breathe new life into these cases.

A Brief History of Climate Non-Refoulement Cases

The principle of non-refoulement is a deeply-cherished tenet of international refugee and international human rights law, and has attained the status of customary international law. Under refugee law, the principle provides that no State may “expel or return (“refouler”) a refugee in any manner whatsoever to the frontiers of territories where his life or freedom would be threatened on account of his race, religion, nationality, membership of a particular social group or political opinion.” Under international human rights law, the prohibition is broader, forbidding return to any State where an individual’s right to life or right to freedom from torture or cruel, inhumane, or degrading treatment or punishment would be under threat. As climate harms have become more acute, courts in immigration cases are increasingly being asked to consider whether sending someone back to a region under significant threat from climate change might violate these prohibitions.

The most prominent case in this area is the UN Human Rights Committee’s 2020 decision in Teitiota vs. New Zealand. Ioane Teitiota and his family were threatened with expulsion from New Zealand to Kiribati, and challenged their removal on the grounds that climate impacts in Kiribati threatened their right to life. After losing on this argument in the New Zealand courts, Teitiota and his attorney brought the case to the UN. The Human Rights Committee set an important global precedent in Teitiota in ruling that  there is a possibility that human rights law might bar returns to places where climate change results in threats to the right to life as contained in Article 6 of the International Covenant on Civil and Political Rights. But in the immediate case of the Teitiota family, the Committee found that the threshold for such a violation had not been met. Importantly, they ruled that the harm in the case was not sufficiently particularized, as everyone in Kiribati faced roughly the same threats, and not sufficiently imminent, as estimates at the time suggested that under current conditions it would be at least 15 years before Kiribati became truly uninhabitable – enough time, in the Committee’s judgment, for the government to act to protect its residents.

Before and since Teitiota, a number of domestic courts have considered similar climate non-refoulement cases. There have been a number of such cases in New Zealand in particular, all of which reached similar results as Teitiota: not ruling out the application of the non-refoulement principle in future cases, but finding it inapplicable to the facts at hand. In Europe, however, there have been more applicant-friendly developments in environmental non-refoulement cases more broadly, with a French appeals court barring the return of an applicant with severe asthma to Dhaka, Bangladesh, given the potential impacts of that city’s air pollution, and Italy’s highest court remanding a case with the instruction that the lower courts consider the human rights impacts of returning someone to the Niger Delta region of Nigeria, given severe environmental damage in that region. Despite this progress, however, no court has yet issued a definitive ruling barring someone from being returned to a place where climate change impacts threaten their right to life. Enter the IACtHR and ICJ.

Climate Change and Non-Refoulement in the IACtHR and ICJ Advisory Opinions

Both of the opinions issued by international courts in recent weeks are advisory opinions, which is to say that they provide instructive interpretations of international law without issuing a ruling in any specific individual case or controversy. Nevertheless, these opinions have the potential to advance the cause of applicants in climate non-refoulement cases.

In their request to the IACtHR for an advisory opinion on State human rights obligations in the context of the climate crisis, Chile and Colombia specifically asked the Court to weigh in on human rights obligations with regard to climate change-related migration. Given this, and given the IACtHR’s long-standing progressive and rights-holder-centric approach to migration more broadly, it is not surprising that the Court devotes a stand-alone section of its Advisory Opinion Number 32 of 2025 (AO-32/25) to migration, under the heading of the “freedom of residence and movement” (paras. 414-434). The Court enumerates several different ways in which climate change can impact the freedom of movement and residence (paras. 416-419), and reiterates its prior observation “that when people are forced to move internationally, they face numerous human rights violations” (para. 420). Because of this, among other obligations, “States are obligated to adopt measures to prevent, in line with the standard of enhanced due diligence, migration and forced displacement resulting directly and indirectly from disasters and other impacts of climate change” (para. 422) and to “develop regulatory, public policy, institutional, and budgetary instruments to address the needs of populations in situations of involuntary mobility” (para. 424). But the Court also considers the possibility of returns in the context of climate change. Specifically, it requires that States “establish an appropriate regulatory framework that provides effective legal and/or administrative mechanisms at the domestic level to guarantee the legal and humanitarian protection of persons displaced across international borders due to the impacts of climate change” and specifies that such a framework should “provide them with protection against refoulement” (para. 433).

The ICJ, by contrast, was not specifically asked to consider climate change-related migration or climate non-refoulement in its Advisory Opinion on international legal obligations in respect of climate change, although migration was raised in inputs to the Court. This makes it all the more striking that the Court not only made reference to climate non-refoulement cases in its opinion, but also chose to highlight this kind of case in the summary of the opinion that was announced from the Bench. For the ICJ, climate non-refoulement is considered under its examination of the right to life (paras. 377-378). After a general paragraph establishing that climate change impacts the right to life (para. 377), the Court devotes a paragraph to non-refoulement, firmly stating that, “[i]n the view of the Court, States have obligations under the principle of non-refoulement where there are substantial grounds for believing that there is a real risk of irreparable harm to the right to life in breach of Article 6 of the ICCPR if individuals are returned to their country of origin.” It should be noted that the entire section of the opinion specifically devoted to human rights is only fifteen paragraphs in total, and the paragraph on non-refoulement is the only one in which the Court makes a definitive pronouncement on a specific genre of climate rights litigation. But what does this mean going forward?

Potential Impacts and Next Steps

Both the ICJ and the IACtHR cite to Teitiota, and neither Advisory Opinion contains any indication that either Court would have broken with the Human Rights Committee on that case. This is one of several areas where the courts could have been more detailed or forceful in their pronouncements. It also remains to be seen generally how States will respond to the Advisory Opinions, and the extent to which they will meaningfully implement the solutions called for. And the protections of the non-refoulement principle, while important, are applicable only to those who have already migrated and face displacement, and are only available on an individual basis. Further, neither ruling provides any guidance on the key questions of imminence and particularity left open by Teitiota and the other climate non-refoulement decisions issued thus far: how immediate do threats to the right to life from climate change have to be, and how specific do they have to be to the applicant in any individual case? Accordingly, there will likely be those who would argue that the new Advisory Opinions do little, or not enough, to advance the law related to climate non-refoulement or climate-related migration more broadly.

Elsewhere, I have argued that the ideal venue to advance the law in this area and answer the imminence and particularity questions is adversarial litigation in regional human rights courts. As I discuss more fully in that piece, these courts have well-established bodies of jurisprudence related to non-refoulement and a strong (and growing) history of considering cases at the intersection of human rights and the environment. Another potential avenue for regional courts to contribute to developing this jurisprudence could come with a recent request for an advisory opinion on climate change presented to the African Court of Human and Peoples’ Rights (ACtHPR). As I emphasized in prior work, while the ACtHPR has heard fewer cases addressing non-refoulement than the other major regional human rights courts, it has addressed the intersection of displacement and environmental harms through its jurisprudence on the right of peoples to a healthy environment contained in Article 24 of the African Charter of Human and Peoples’ Rights. The ACtHPR also has wide latitude to consider multiple sources of law in its rulings, and will surely be able to draw on both the ICJ and IACtHR Advisory Opinions in making its climate ruling. Regional courts are limited in that they must wait for appropriate cases to be brought, having had domestic remedies exhausted, and they have faced compliance challenges. However, they have the advantage of being able to consider the specificities of regional contexts (recognizing that most cross-border migration still happens within geographically-proximate regions). This is particularly important given that most climate change-related migration happens within the Global South, such that the regional perspective and specificities of the ACtHPR and IACtHR take on special weight in this area. At the same time, these courts offer legal interpretations with persuasive value beyond national borders, and engage in productive exchange with one another, domestic courts, and other international courts like the ICJ. In making specific reference to the need to ensure non-refoulement in the context of climate change, the IACtHR cements its status as a venue ripe for this kind of case.

Further, while they may not provide significant guidance on open legal questions regarding climate non-refoulement, the reference to this issue in both Advisory Opinions suggests more broadly that these cases are still ripe for examination. Trends in climate and human rights litigation since Teitiota have tended in other directions, with particular focuses on ensuring sufficiently ambitious climate action and addressing corporate wrongdoing. These kinds of litigation remain crucial, and there is rich support for litigants in such cases, as well as a number of other forms of climate and human rights litigation in the Advisory Opinions. But climate non-refoulement litigation should not be neglected. It does not provide all of the solutions to the human rights abuses associated with climate change-related migration, but it does have the potential to impact the lives of a number of individuals threatened with return to climate harms and to contribute to significant advancements in climate change law and policy. The International Court of Justice and the Inter-American Court of Human Rights would seem to agree.