Judicial conversations and interactions take place in different settings – sometimes behind closed doors, sometimes out in the open. One open form of conversation is the use of comparative analysis in legal arguments. Focusing on comparative arguments in policy discussions on the right to a healthy environment within the Council of Europe, I will argue that comparative arguments are too often cursory and superficial and that calls for the transferral of elements from one human rights system to another tend to underestimate the complexities involved in such legal transplants. Unless the discipline of comparative human rights law is further developed and relied upon, too much risks being lost in translation between different legal systems.

The right to a clean, healthy and sustainable environment v. the greening of “traditional” human rights

The right to a clean, healthy and sustainable environment (from now on “right to a healthy environment”) is recognized in one form or another in legal systems at national, regional and international level. It is explicitly contained in the African Convention of Human Rights, the Arab Charter on Human Rights and the Protocol of San Salvador to the American Convention on Human Rights. It has been recognized through resolutions of the UN Human Rights Council and the UN General Assembly. Recently, its existence has been confirmed by the International Court of Justice in the Advisory Opinion on Obligations of States in respect of Climate Change. The European Convention on Human Rights in contrast, does not contain the right.

In policy discussions, comparative analysis unfortunately often ends here. Its results are used to contend that the European human rights system is lagging behind and that the European Court of Human Rights lacks the means to effectively counter the triple planetary crises of pollution, climate change, and loss of biodiversity.

This kind of formalistic comparative analysis, however, overlooks the fact that the European Court of Human Rights has found ways to address environmental degradation on the basis of existing Convention rights despite the absence of a right to a healthy environment in the Convention.

In one of the first leading environmental cases, the 1994 case of López Ostra v. Spain, the Court recognized that severe environmental pollution may affect individuals’ well-being in such a way as to violate their private and family life protected under Article 8 ECHR. This case and others have set the scene for the development of an extensive jurisprudence by the Strasbourg Court on human rights and the environment. The Court’s case-law guide on the environment lists more than 260 judgments and decisions ranging from exposure to nuclear radiation and noise emanating from wind energy farms to water contamination and waste management. This so-called greening of Convention rights is a testament to the nature of the Convention as a living instrument. It culminated in the Klimaseniorinnen judgment of 2024 in which the Court held that Article 8 encompasses a right to effective protection from serious adverse effects of climate change on individuals’ life, health, well-being and quality of life.

Compared to the sweeping pronouncements of the Inter-American Court of Human Rights in its recent Advisory Opinion on climate emergency and human rights for example, the implications of this jurisprudence may not be as evident and may seem difficult to grasp at times. The Strasbourg Court does not determine the scope of human rights obligations in abstracto nor does it set out jurisprudential guidelines on a particular topic in advisory opinions of the kind found in the Inter-American or the African system. Instead, the ECtHR shapes human rights law through individual cases. The broader picture takes time to emerge.

A formalistic comparative approach also fails to take into account the Convention’s real-life impact on environmental protection in Europe. The environment-related ECtHR judgments have not remained abstract legal pronouncements, but have led to real improvements on the ground. Although shortcomings in the execution of ECtHR judgments exist and even if the execution process is not always without difficulty as the current discussions on the execution of the Klimaseniorinnen judgment demonstrate, in general, the Council of Europe execution system works well, in particular when compared to other human rights systems: The overwhelming majority of environment-related judgments has been implemented under the supervision of the Committee of Ministers, some through adjustments in administrative practices or in jurisprudence, others through legislation, not only to the benefit of the individual applicant but to the benefit of environmental protection in the respective state in general.

In terms of the sheer number of environment-related decisions and the resulting change on the ground, the European system is unique and very successful. This essential perspective gets lost if comparative analysis is limited to noting the existence of the right to a healthy environment or its absence in a human rights system.

Inclusion of the right to a healthy environment into the European Convention on Human Rights?

Nevertheless, the Court’s environment-related jurisprudence is constrained by the boundaries set by the Convention: For the ECHR, environmental degradation is only relevant where it has a direct harmful effect on individuals’ Convention rights. The environment as such does not enjoy protection under the Convention. The Convention’s territorial boundaries find application as well as the Court has clearly set out in the Duarte case.

So what if the right to a healthy environment was included into the ECHR? It has been argued inter alia by the Council of Europe’s Parliamentary Assembly and a broad coalition of civil society organisations that the inclusion of the right to a healthy environment into the Convention is necessary to allow the Court to effectively counter pollution, climate change and loss of biodiversity. The question is currently being debated within the Council of Europe. A study on the need and feasibility of further instruments on human rights and the environment has been drafted by the Steering Committee on Human Rights and presented to the Committee of Ministers at the end of 2024. The study lays out a variety of options with arguments for and against that range from not changing the status quo to adopting Additional Protocols to the ECHR and/or the European Social Charter containing the Right to a Healthy Environment. It is now up to the Committee of Ministers to decide on the way forward. So far, however, there is no indication of an emerging consensus in one direction or another.

Assuming that a political consensus on the need to include the right to a healthy environment in the ECHR system emerges, the operational implementation seems to be straightforward at first sight and to consist in the simple transfer of a right that is already in existence elsewhere into the ECHR. But here again, a closer look reveals complications.

First of all, while the right to a healthy environment is recognized broadly, there are competing visions about its content and scope. Two recent Advisory Opinions on climate change, one from the Inter-American Court on Human Rights, the other from the International Court of Justice demonstrate that there is no common understanding of the right to a healthy environment in international law. The Inter-American Court on Human Rights considers that the right protects Nature as such, even in the absence of risks to individuals. In the Inter-American system, the right belongs to present and future generations, applies extraterritorially and needs to be articulated with the protection of the rights of Nature itself. The Inter-American Court also seems to consider that at least elements of the right have jus cogens status. In contrast, the ICJ Advisory Opinion on obligations of States in respect of climate change does not qualify the right as jus cogens or even as customary international law. The question whether the right protects the environment as such is not addressed. But the Opinion stresses that the right to a healthy environment is essential for the enjoyment of other human rights and inherent in them. This points to an understanding of the right to a healthy environment as a generic right that encompasses environmental aspects of existing human rights, regrouping them under a new heading without adding anything new. In a nutshell, the two Advisory Opinions contain fundamentally divergent conceptions of the right to a healthy environment with significant practical implications.

There is a second reason why it is not as simple as one might assume to include a right that is already part of other human rights systems into the Convention: Just like an organ transplant, a legal transplant is a highly complex operation. The legal mechanism that is being transplanted needs to be adapted to the receiving legal system. In this case, the right to a healthy environment’s meaning and scope must be adapted in such a way as to smoothly fit into the Convention system.

There are many aspects that need to be considered in that respect: How does the idea that the right to a healthy environment protects the environment as such fit into a Convention system based on individual rights enforceable through individual applications? How would the right relate to the Court’s existing environment-related jurisprudence? Would the right to a healthy environment transform every case of environmental degradation into a Convention issue? Or would it presuppose a specific connection of the applicant to the environmental degradation in question?

Highlighting these issues does not imply that the right to a healthy environment cannot or should not be added to the Convention system. These questions serve to show the complexity of the task and demonstrate that human rights comparison “light” is not sufficient. If comparative human rights analysis is meant to be meaningful, it is necessary to look into the details and to understand in which ways legal concepts are shaped by the human rights system they are embedded in. This requires a sound comparative methodology. In all of these respects, there is room for improvement – in the institutions and courts, in academia and also in practice. Common efforts are needed unless we want to risk being lost in translation for a long time.

The views in this contribution are solely those of the author, and do not necessarily reflect the views of any institution with which the author is or has been affiliated.