Climate Justice through International Courts and Tribunals: Advisory Opinions in the International Tribunal on the Law of the Sea (ITLOS), the Inter-American Court of Human Rights (IACtHR) and the International Court of Justice (ICJ)

This Preface to the EPL Special Issue 55 (6) 2025 on the Advisory Opinions (2024-2025) of the International Courts and Tribunals (ICTs) onClimate Change seeks to provide an overview and serves as a lead research article to introduce the legal trajectory adopted for seeking an authoritative view on the “obligations of the States” under international law and “legal consequences under these obligations for States” (worded differently before each ICT) in relation to climate change from the three ICTs. The three marathon processes for seeking Advisory Opinions (AOs) took place before the International Court of Justice (ICJ), Inter-American Court of Human Rights (IACtHR) and International Tribunal on the Law of the Sea (ITLOS). The fourth one is pending (since May 02, 2025) before the African Court of Human & Peoples’ Rights. The respective ‘requests’ were presented to these ICTs on May 29, 2023 (ICJ), January 9, 2023 (IACtHR) and December 12, 2022 (ITLOS). After going through their procedural craft of formal requests, written statements, oral presentations and specially arranged meetings (by the ICJ) with some stakeholders such as Intergovernmental Panel on Climate Change (IPCC), the three ICTs delivered their respective AOs on July 23, 2025 (ICJ, The Hague), July 03, 2025 (IACtHR, San Jose) and May 21, 2024 (ITLOS, Hamburg). Thus, the AOs of these three ICTs provide a unique legal corpus ostensibly for strengthening legal basis of the State-centric consensual regime (1992 UNFCCC, 1997 Kyoto Protocol and 2015 Paris Agreement) on climate change. These AOs have brought to the fore role of the ICTs as ‘sentinels’ even as entire climate change global regulatory process (1992-2025) seem to be floundering after 33 years in spite of grim scientific projections about the “climate emergency”. It is in this backdrop that this preface-cum-research article provides the context, a preliminary overview of the outcomes of the three ICT AOs and possible future trajectory to resolve the “climate conundrum”, beyond the three AOs.

Resumen: Este artículo examina cómo los procesos consultivos se han convertido en un mecanismo de participación y acceso a la justicia climática para los defensores de intereses de las generaciones futuras. En la primera parte, se analizan los fundamentos normativos de la protección intergeneracional desde el marco de la sostenibilidad y los derechos humanos. En la segunda parte, se estudia la cuestión desde la perspectiva práctica, el rol de los actores no estatales en los procesos consultivos sobre cambio climático ante la Corte Internacional de Justicia (CIJ) y la Corte Interamericana de Derechos Humanos (CtIDH). Esta sección analiza el caso del movimiento World Youth for Climate en el marco de la CIJ y el uso del mecanismo de Amicus Curiae ante la CtIDH. Finalmente, se plantean reflexiones sobre el grado de participación y el impacto potencial de estas iniciativas para ampliar el espectro de protección de intereses de las generaciones futuras desde los derechos humanos frente a la crisis del cambio climático. Abstract: This article examines how advisory proceedings have become a mechanism for participation and access to climate justice for advocates of the interests of future generations. The first part analyzes the foundations of intergenerational protection in response to the human rights crisis caused by climate change. In the second part, the issue is studied from a practical perspective: the role of non-state actors in advisory proceedings on climate change before the International Court of Justice (ICJ) and the Inter-American Court of Human Rights (IACtHR). This section examines the case of the World Youth for Climate movement within the ICJ framework and the use of the Amicus Curiae mechanism before the IACtHR. Finally, reflections are offered on the degree of participation and the potential impact of these initiatives to broaden the spectrum of human rights protection of future generations in the face of the climate change crisis. Palabras clave: Derechos Humanos. Cambio Climático. Futuras Generaciones. Actores no Estatales. Keywords: Human Rights. Climate Change. Future Generations. Non-State Actors. Índice: 1. Introducción 2. Fundamentos de la protección intergeneracional ante la crisis climática 2.1. El cambio climático: una crisis de derechos humanos 2.2. El desarrollo sostenible y su conexión con los derechos humanos desde una perspectiva intergeneracional 3. Oportunidades de acceso a la justicia climática de las futuras generaciones en procesos consultivos sobre derechos humanos: una mirada hacia el movimiento climático juvenil y los amicus curiae 3.1. World Youth for Climate Justice: el movimiento transnacional que intenta redefinir el acceso de actores no estatales ante la Corte Internacional de Justicia 3.2. El amicus curiae ante la Corte Interamericana de Derechos Humanos: su contribución a la transformación del acceso a la justicia para las futuras generaciones 4. Conclusiones 5. Bibliografía Index: 1. Introduction 2. Foundations of intergenerational protection in the face of the climate crisis 2.1. Climate change: a human rights crisis 2.2. Sustainable development and its connection to human rights from an intergenerational perspective 3. Opportunities for access to climate justice for future generations in advisory proceedings on human rights: an approach to the youth climate movement and amicus curiae 3.1. World Youth for Climate Justice: the transnational movement that seeks to redefine the access of non-state actors before the International Court of Justice 3.2. The amicus curiae before the Inter-American Court of Human Rights: its contribution to transforming access to justice for future generations 4. Conclusions 5. Bibliography

The Nuremberg tribunal was the expression and the beginning of states' recognition of their duty to prosecute genocide and other gross human rights violations. It was a first step towards fulfillin...

This article examines the advisory proceedings in relation to climate change before the International Court of Justice, the International Tribunal for the Law of the Sea, and the Inter-American Court of Human Rights through the lens of the broader phenomenon of public interest litigation. It focuses on certain substantive, institutional, and procedural dimensions of the advisory proceedings, construed as a form of public interest litigation. First, it argues that international courts and tribunals should innovate by allowing broader participation while considering the constraints of their statutes and rules of procedure. Second, this article examines how prior advisory opinions, even though non-binding, may shape the subsequent practice of States, and considers the impact that the advisory opinions on climate change may have. Ultimately, this article questions whether these advisory opinions may have a catalytic effect on ensuring the protection of other global commons in the future.

Regional human rights courts like the European Court of Human Rights (ECtHR), the Inter-American Court of Human Rights (IACtHR), and the African Court of Human and People's Rights (ACtHPR) have become popular sites of mobilization for victims and activists who seek justice when justice fails at home. Besides being platforms for individual remedy, human rights courts increasingly shape social norms and state policy within countries, making them attractive avenues for rights advocates to develop new norms or to push domestic authorities to reform legislation. The judges of these courts can decide, for example, whether same-sex couples have a right to be married, if prisoners have the right to vote or receive HIV/AIDS treatment, or when a state can deport illegal immigrants to a country where they will likely be tortured. As these courts pass their judgments, they often find themselves in conflict with states that are violating human rights of marginalized groups on a large scale and are unwilling to implement international rulings. Although international human rights courts have become increasingly popular venues among victims and activists who seek justice when justice fails at home, we are only beginning to understand how activists play roles in shaping the development of regional human rights courts' case law—the body of judgments that shapes how judges will make their decisions in the future. We now have plenty of international relations and international legal research on the interactions between states and international courts: how judges in these courts wrestle between deferring to the interests of member state governments whose actions are on trial and sticking closely to the conventions' fundamental yet evolving principles (Alter et al., 2019; Helfer & Voeten, 2014). As some states begin to resist international courts' authority, scholars have begun to examine the dynamics of this backlash (Hillebrecht, 2022; Madsen et al., 2018; Sandholtz et al., 2018). Recent studies have also demonstrated that human rights advocates—whether NGOs or individual lawyers—have a significant impact on shaping the jurisprudence of international courts and the impact judgments have in concrete locations (Kahraman, 2018; Sundstrom, 2014; van der Vet, 2012; Kurban, 2020; Conant, 2018; Harms, 2021; Cichowski, 2016; Hodson, 2011; Haddad, 2018). Meanwhile, these advocates themselves have been subject to repression and stigmatization by governments as part of the backlash phenomenon. Without an adequate understanding of the factors shaping activists' engagement with international courts, we risk undervaluing their strategic impact on the expansion of case law, the human rights protection of marginalized groups who cannot find remedies at home, and the domestic implementation of these judgments in an age of state backlash. In this section, we summarize the three papers contained in this symposium and their original contributions to these themes. Over the last decade, dozens of countries have erected legal barriers or started vilifying campaigns to stymie the work of NGOs (Buyse, 2018; Chaudhry, 2022). One tactic in this toolkit is the enactment of burdensome regulation on NGOs that receive funds from foreign donors as they allegedly promote foreign agendas (Christensen & Weinstein, 2013; Dupuy et al., 2021). States that frequently abuse human rights are especially prone to target NGOs that engage in strategic litigation (Hillebrecht, 2019). Most NGOs depend on foreign funding, and NGOs that litigate international cases fall disproportionately in this category, but do funders affect the selection of cases? In “Foreign Agents or Agents of Justice? Private Foundations, NGO Backlash, and International Human Rights Litigation,” Heidi Haddad and Lisa Sundstrom examine the extent to which Western donors, particularly private foundations, have encouraged NGOs in Europe to litigate at the ECtHR as a human rights advocacy strategy. They examine overall patterns of donor funding and NGO litigation records, and look in more detail at the case of Russian NGOs' foreign funding and litigation records. The analysis is extremely timely, as the Russian government's criminalization of independent civil society actors, especially in the human rights field, and their accusation that foreign funding turns NGOs into “foreign agents” have been crucial elements of the Russian regime's autocratization. This claim has also provided fuel for Russia's disenchantment with the ECtHR in recent years, contributing to the assessment of many observers that Russia's full-scale attack on Ukraine was the last straw in an inevitable collision course leading to its exit from the Council of Europe. Haddad and Sundstrom debunk the idea that foreign donors are pushing NGOs toward strategies of human rights litigation. Instead, they argue, there is more evidence that NGOs themselves promoted the mechanism of international litigation as a strategy that donors later adopted. This article is a poignant reminder of the advocacy tools that Russian human rights activists and citizens have lost as a result of their government's departure from the Council of Europe, including ECtHR jurisdiction. Yet it also provides insight into the likely roles of foreign donors in other country cases where NGOs are using international court litigation as a human rights advocacy strategy, which is often a target of the ire of national governments, as explored in the next article in the symposium. When states attack human rights NGOs within their borders and/or international human rights courts themselves, how does this affect the willingness of those NGOs to take cases to international courts, and the ways in which they do so? De Silva and Plagis ask this question in their article about state backlash against NGOs in the case of Tanzania and the African Court on Human and Peoples' Rights. A fascinating empirical question they pose is: does state backlash against NGOs increase NGO litigation at international courts (to contest state repression at those courts and use international mechanisms when domestic ones are not available), roughly in line with Keck and Sikkink's famous “boomerang pattern” (Keck & Sikkink, 1998), or decrease it due to heightened fear and restricted NGO capabilities that state repression creates? Employing a process-tracing analysis of NGOs' involvement in three cases before the African Court at different stages of the Tanzanian government's backlash against the Court, De Silva and Plagis find that “two-level backlash” by states can result in both phenomena, either promoting or deterring NGO legal mobilization at international human rights courts, depending on certain conditions. The three selected cases concerning the death penalty, the rights of persons with albinism, and the rights of pregnant schoolgirls and mothers, which took place at different time periods, demonstrate a number of patterns of state backlash interacting with NGO strategies. The authors find that domestic-level state backlash deterred domestic NGOs from partnering with international NGOs in litigation, but that such backlash, when it repressed domestic political and legal mobilization opportunities, actually encouraged both Tanzanian and international NGOs to turn to the African Court more frequently to seek remedies. International-level backlash in turn only deterred NGOs from international litigation when such backlash consisted of state efforts to restrict NGOs' ability to engage in litigation, and not when the international backlash was in the form of routine noncompliance with African Court rulings. Importantly, the authors find that NGO responses to state backlash were significantly shaped by their degree of legal consciousness and expertise with the rules, proceedings, and workings of the African Court. Those NGOs with less knowledge and experience were more likely to back away from engaging with the Court under the pressure of state backlash. De Silva and Plagis conclude that “NGOs' persistent human rights advocacy in the face of state backlash is a double-edged sword,” in the sense that they may not be deterred by state backlash initially, but there is a danger that their continued determination to engage in international litigation could prompt governments to engage in even more severe forms of backlash, with critical impacts on international courts and already vulnerable human rights defenders. Rights advocates have a growing menu of institutions and courts available to them. How do activists choose at which institution to lodge their cases in a world where legal remedies have diversified, or as some have argued, fragmented (Koskenniemi & Leino, 2002)? In “What Makes an International Institution Work for Labor Activists? Shaping International Law through Strategic Litigation,” Filiz Kahraman goes beyond the tendency of legal mobilization studies to only examine how activists interact with a single court or institution. Instead, Kahraman opens up how rights advocates imagine which institution is most receptive to their claims. Drawing on a comparative interview study of British and Turkish trade union activists and their legal mobilization campaigns at international courts and quasi-judicial institutions like the International Labor Organization (ILO), Kahraman examines how activists first probe and then strategically identify which court or international institution is most susceptible to their primary goals of influencing structural reforms and setting new norms. Through this probing process—or dynamic signaling game between courts and litigants—activists push a court's jurisprudence and case law into new issue areas. For instance, at the ECtHR, Turkish trade unionists challenged domestic courts' ruling that public sector workers did not have the right to establish unions, even though the ECtHR had no established case law on labor rights in 1990s. They won the case, with the ECtHR finding that Turkey violated the right of public sector workers to unionize. These cases not only had an impact within Turkey, but over the next decades, similar cases brought by British unionists would spin off the early precedent set by the Turkish legal mobilization efforts. Kahraman argues that they ultimately pushed the ECtHR to recognize the basic trade union rights as fundamental human rights. Kahraman sheds light on the often hidden strategies behind international litigation. Activists litigate not just for the immediate impact on the current case they work on, but how they envision that all the cases they work on may shape norms and domestic structural reforms further in the future. Whether an institution is perceptive of claims lies in the eye of the beholder. Kahraman finds that besides targeting institutions with high compliance rates, they also take cases to institutions with low rates of compliance, especially “if these institutions have extensive judicial authority to create new international norms.” So, it is not the de jure protection set by an international courts, but rather how activists perceive the juridical responsiveness and judicial authority of courts—or, how judges adopt either an activist approach or restraint in response to incoming cases and how willing states are to implement cases of a court, respectively—that determines why activists select certain courts or quasi-judicial institutions (like the ILO). Kahraman gives us new tools to interpret how activists perceive authority and receptiveness and respond to opportunities. Rather than static external legal remedies, courts and quasi-judicial institutions are opportunity structures that are malleable to the strategic vision of the activist or litigant. The articles in this symposium together reveal a number of key overlapping insights. At the broadest level, they demonstrate that activists' behaviors and strategies influence international courts' jurisprudence, politics within states, and the human rights outcomes of everyday citizens—and these influences have often been hidden in our existing canon of research on international courts. In addition, all of these articles show that, while activists may face challenges in their efforts, often including significant backlash from their home state governments, they also continue to retain significant agency through their creative efforts to develop legal strategies and circumvent state repression. Activists perennially innovate: sparking the ideas that inspire donors who fund them; calculating how to continue their litigation work when government actors threaten them; and taking risks in litigation to push courts to expand how they define human rights. However, along with these uplifting conclusions, there are worrying patterns that demand future research. States are increasingly pushing back against the powers of international courts to bind them to costly measures, and as this symposium has shown, national governments often point to activists as contributors to this “problem” of invasive international human rights standards. A growing body of research has tracked how human rights defenders of all kinds globally are under threat from actors like governments and corporations who disagree with their contentious actions. We need more studies that gather comprehensive data and systematically track these threats, specifically with regard to activists who engage in international human rights litigation. We suspect that such activists are likely disproportionately targeted due to the international visibility of their complaints. We also desperately need research into possible innovative responses to these threats to activists—responses from activists, funders, governments of countries that support human rights, and international courts themselves. Freek van der Vet is a University Researcher at the Erik Castrén Institute of International Law and Human Rights, Faculty of Law, University of Helsinki and the principal investigator of the Toxic Crimes Project. Lisa McIntosh Sundstrom is Professor of Political Science at the University of British Columbia. She is the director of the ActinCourts network at UBC and conducts research on legal mobilization by Russian activists.

for Scopus Indexing: In May 2024, the International Tribunal on the Law of the Seas (ITLOS) issued a historic advisory opinion on the obligations of States regarding climate change under the United Nations Convention on the Law of the Seas. This advisory opinion was issued in response to a request submitted by the Commission on Small Island States on Climate Change and International Law. Significantly, the Tribunal stated that: a) States must interpret their obligations under the Convention in light of the best available science; b) greenhouse gas (GHG) emissions constitute pollution of the marine environment; and c) they must take all necessary measures to reduce, prevent and control GHG emissions. ITLOS also noted that developed States have an obligation under the Convention to assist developing States in mitigating the effects of climate change. This advisory opinion marks an important first step in the fight for climate justice for small island States. Forthcoming are advisory opinions concerning climate change from the International Court of Justice (ICJ) and the Inter-American Court of Human Rights (IACHR). In this article, we explore the jurisdictional arguments some participants raised, the significance of the Tribunal’s opinion, and we contextualize the opinion in light of broader efforts towards climate justice.

INTRODUCTION. The article examines the historical establishment of the United Nations Framework Convention on Climate Change (UNFCCC) and its role as the foundational framework for the international climate legal regime. The study highlights the importance of the choices made during the drafting of the Convention, analyzing their long–term impact on global climate governance. The research explores the events leading up to the Earth Summit (Rio Conference) in 1992, where the UNFCCC was adopted, and investigates how its fundamental principles and obligations shaped subsequent climate policies, including the Kyoto Protocol and the Paris Agreement. The study aims to contextualize the Convention within the broader historical and legal developments in international environmental law.MATERIALS AND METHODS. The research follows a qualitative legal–historical approach, utilizing primary sources, including treaty texts, General Assembly resolutions, advisory opinions from international courts, and official conference proceedings. Additionally, secondary sources, such as academic commentary, environmental law textbooks, and journal articles, provide insights into the evolution of international climate law. The study is divided into two key phases. 1. Historical Analysis: A chronological examination of the negotiations preceding the UNFCCC, focusing on the Stockholm Conference (1972), the Montreal Protocol (1987), and scientific reports from the Intergovernmental Panel on Climate Change (IPCC). 2. Legal Framework Analysis: An evaluation of the legal principles enshrined in the UNFCCC, such as sustainable development, common but differentiated responsibilities (CBDR), and intergenerational equity, as well as an assessment of its institutional mechanisms, including the role of the Conference of the Parties (COP).RESEARCH RESULTS. The UNFCCC as a Normative Framework: Despite being considered a “framework convention” with broad and non– binding commitments, the UNFCCC introduced fundamental legal principles that later became the cornerstone of climate governance. Legal Innovations and Institutionalization: The Convention established a system of cooperation among states, creating institutional mechanisms such as the COPs, which facilitated continued legal evolution in climate governance. The establishment of the UNFCCC Secretariat further institutionalized climate negotiations. Enduring Influence on International Law: The Convention remains a reference point for climate litigation and international advisory opinions, particularly in recent cases before the Inter–American Court of Human Rights and the International Tribunal for the Law of the Sea. These legal bodies have increasingly drawn upon UNFCCC principles to determine states' obligations concerning climate change.DISCUSSION AND CONCLUSION. The article concludes that the UNFCCC, despite its perceived initial weaknesses, has proven to be a resilient and foundational legal instrument in international climate governance. The Convention's principles and procedural mechanisms have enabled the development of binding legal commitments, such as those found in the Kyoto Protocol and the Paris Agreement. Moreover, its flexible institutional design has allowed it to adapt to emerging challenges, such as climate litigation and advisory proceedings in international courts. Looking forward, the UNFCCC is expected to continue shaping future legal obligations related to climate action, particularly as climate disputes become more prominent in international judicial bodies. The study underscores the ongoing relevance of the UNFCCC in the face of evolving environmental challenges, reaffirming its status as the standard framework for global climate governance.

Climate change increasingly affects various aspects of human activity each year, resulting in growing transboundary damage. Consequently, the author aims to analyze the obligations of states to prevent transboundary damage, drawing on the 1982 UN Convention on the Law of the Sea and the principles of customary international law. The article examines the obligations of states under the 1982 UN Convention on the Law of the Sea, with a particular focus on the principles of prevention of transboundary damage and due diligence, as well as their interrelationship. To deepen the understanding of due diligence within the context of international environmental law and climate change, the author analyses both the position of the Commission of Small Island States on Climate Change and International Law on due diligence, as well as the Advisory Opinion of the International Tribunal for the Law of the Sea on the request of the Commission of Small Island States. In examining the ITLOS Advisory Opinion, the positions of States on climate change and its impact on public order and life are also explored. Currently, there is a discernible trend towards increased climate litigation and the development of international environmental law, as evidenced not only in the multitude of disputes before national and international courts but also in the pending Advisory Opinions before the International Court of Justice and the Inter-American Court of Human Rights. The article also discusses the problem of determining the existence of international legal liability for transboundary damage and explores the ways and forms of redress. In situations involving transboundary damage, the affected state, as the victim, must prove a wrongful act, namely a breach of an international obligation, attributable to the other state. Thus, the paper analyzes the obligations of states to prevent transboundary damage, using the law of the sea as an illustrative example, and also raises the issue of state liability.

Climate Justice through International Courts and Tribunals: Advisory Opinions in the International Tribunal on the Law of the Sea (ITLOS), the Inter-American Court of Human Rights (IACtHR) and the International Court of Justice (ICJ)

The International Courts Project, M.W. Janis. Part 1 The classical universal institutions: peaceful settlements of disputes, L.B. Sohn the Hague peace conferences of 1899 and 1907, D.J. Bederman the international court, M.W. Janis the Hague Permanent Court of Arbitration, W.E. Butler inter-state arbitration since 1945 - overview and evaluation, C. Gray and B. Kingsbury. Part 3 The regional international courts: the Court of Justice of the European Communities and the prospects for international adjudication, J.W. Bridge the European Court of Human Rights, M.W. Janis the Inter-American Court of Human Rights, C.M. Cerna. Part 3 Specialized international tribunals and procedures: the glorious past and uncertain future of international claims tribunals, D.J. Bederman the mandatory component in the CSCE dispute settlement system, K. Oellers-Frahm the case for an international court of criminal justice and the formulation of international criminal law, J.W. Bridge international legal aid - the Secretary General's trust fund to assist states in the settlement of disputes through the International Court of Justice, M.E. O'Connell the Law of the Sea Tribunal, M.W. Janis.

The recent advisory opinions on climate change by the International Court of Justice, the Inter-American Court of Human Rights and the International Tribunal for the Law of the Sea, alongside the European Court of Human Rights’ decision in Klimaseniorinnen, extend their legal implications to international tax law. These implications reach well beyond tax measures that directly impact mitigation, such as exemptions for fossil fuels. According to these pronouncements, the obligations under the Paris Agreement, the customary duty to prevent significant environmental harm and other applicable law, oblige states to undertake tax reforms within their national circumstances when necessary to ensure the fiscal adequacy of domestic climate measures. Also, the duty to cooperate requires states to better align international tax rules with climate objectives. Amending tax treaties to reflect climate objectives – such as introducing variable withholding tax rates or capital gains taxing rights based on environmental concerns – deserves consideration. Through the prism of climate legal obligations, the influence of international law – including customary international law previously considered of limited efficacy in constraining tax sovereignty – is substantially strengthened within the tax domain.

Currently, there are pending requests for advisory opinions regarding State obligations on climate change before both the International Court of Justice (ICJ) and the Inter-American Court of Human Rights (IACtHR). Additionally, the International Tribunal for the Law of the Sea (ITLOS) recently issued its advisory opinion on Climate Change and International Law on 21 May 2024. This article aims to compare these requests, analysing their contextual backgrounds and the extent of States’ involvement in the advisory proceedings. The aim is to examine the jurisdictional scope and future prospects of the proceedings before the two courts and the tribunal by exploring the distinct normative, practical and political strategies shaping each request. Furthermore, the article assesses how these factors influence the framing of the requests for advisory opinions and shape the contributions received by interested States. By providing a holistic analysis of these legal interpretations, the author evaluates the potential impact of the aforementioned opinions on the future behaviour of States and the development of international law. Ultimately, this analysis aims to inspire the progress of strategic climate change litigation and inform about potential enhancements in the interpretation and development of future international agreements.

International law governing the settlement of disputes through law-based forums, such as courts, tribunals and arbitral tribunals, is fraught with limitations that are becoming especially apparent with respect to disputes that involve the protection of the environment. However, despite the deficiencies of the law, international courts and tribunals have issued judgements in disputes involving the protection of the environment. At the global level, the International Court of Justice (ICJ), the Appellate Body of the World Trade Organization (WTO) and the Tribunal for the Law of the Sea (ITLOS) have handed down decisions in relevant cases. In addition, other legal forums can also be called upon to decide cases involving international environmental law. Such forums include the Environmental Chamber of the ICJ and the Permanent Court of Arbitration (PCA) under its general facilities and under the Environmental Facility that it is planning to establish. Similarly, special bodies, such as the United Nations Compensation Commission (UNCC), may decide on cases. Moreover, regional forums such as the European Court of Human Rights (ECHR), the Inter-American Court of Human Rights and the Court of Justice of the European Community (ECJ) have ruled on cases involving international environmental law. Despite the these developments, calls for the establishment of an international environmental court at the global level persist. Several arguments have been advanced to justify the establishment of an international environmental court, for example the very many pressing environmental problems that exist today and the need for a bench consisting of experts in international environmental law to consider these problems, the need for individuals and groups to have access to environmental justice at the international level, the need to enable international organizations to be parties to disputes related to the protection of the environment and the need for dispute settlement procedures that enable the common interest in the environment to be addressed. Arguments against the establishment of an international environmental court have been advanced as well. This publication explores the arguments for and against the establishment of an international environmental court, examining topics such as the definition of an international environmental dispute and the concomitant expertise required on the bench, fragmentation and its root causes, access to justice and the representation of community interests. The author argues that the establishment of an international environmental court is not the most desirable option and she suggests that it might be more fruitful if we consider developments in environmental law, as well as in other relevant areas of international law, from a different perspective, namely, that of administrative law, and reassess the relationship between international and national law. Such an approach, she argues, is warranted if, inter alia, viable means for resolving environmental disputes that may arise are to be identified.

Can the Advisory Opinion Strengthen the International Response to Climate Change?

This article analyses three noteworthy aspects of the 2024–2025 Advisory Opinions (AOs) on climate change from the International Court of Justice (ICJ), the International Tribunal for the Law of the Sea (ITLOS), and the Inter-American Court of Human Rights (IACtHR). Primarily, the article considers what the three AOs suggest about the variable, fact-dependent content of the various obligations to exercise due diligence falling upon States. It is argued that while the content of due diligence obligations varies depending upon various context-specific factors, including the capabilities of the State concerned, this does not lead to unmanageable indeterminacy nor provide excuses for climate inaction based on national circumstances. Rather, these international courts and tribunals (ICTs) have provided significant guidance on objectively reasonable approaches to implementing the relevant obligations and have emphasised that applying due diligence standards is a matter for objective determination. Secondly, the article considers what the AOs suggest about the continuing nature of States’ obligations to cooperate, which are not exhausted by specific climate-related treaties or processes. Third, the article demonstrates that all three AOs recognise and elaborate upon a duty of States to regulate effectively the activities of private, non-State actors that cause climate change.