Leer en español aquí.
The first part of this article reflects on how tragedies resulting from climate change tend to reshape our understanding of law in general and human rights law in particular. The second part discusses some precedents from universal and regional human rights systems, with an emphasis on the main contributions of Advisory Opinion AO-32/25, titled “Climate Emergency and Human Rights”, recently adopted by the Inter-American Court of Human Rights (IACtHR). In this third and final part, I analyze some of the reasoning gaps in the sections of the advisory opinion entitled “The Protection of Nature as a Subject of Rights” and “The jus cogens Nature of the Obligation Not to Cause Irreversible Damage to the Climate and the Environment.” Several of these gaps were noted in the dissenting opinions of the Court’s President, Judge Nancy Hernández López, and Judge Patricia Pérez Goldberg.
The Protection of Nature as a Subject of Rights
The title of this section of AO-32/25, and the chapter in which it appears (“Obligations Derived from Substantive Rights”), seem to suggest the possibility that Nature itself could be a victim of violations of the American Convention on Human Rights (ACHR). However, its considering paragraphs are ambiguous and refer to Nature indiscriminately as both a “subject of rights” and a “collective subject public interest” (para. 281). The section highlights the importance of “moving toward a paradigm that recognizes ecosystems as rights-holders” (para. 279) and the compatibility of such an approach “with the general obligations to adopt domestic legal measures” (para. 281). It also cites laws and court rulings from several countries that recognize Nature as a bearer of rights (para. 286).
The advisory opinion acknowledges “the efforts undertaken at the international level to promote an integrative perspective to the protection of Nature” (para. 284). However, the cited efforts only enshrine the intrinsic value of biological diversity and the need to “achieve a world in which humanity lives in harmony with nature” (para. 285), among other commitments to preserve and protect Nature that do not amount to its recognition as a rights holder. In other words, the IACtHR appears to rely on a myriad of international instruments and initiatives¹ to invoke a right that those same precedents do not enshrine.
Among the other legal imprecisions, the advisory opinion asserts that:
“[…] in accordance with Article 29 of the American Convention, the interpretation of the rights protected within the Inter-American system must be guided by an evolutionary perspective, consistent with the progressive development of international human rights law. In this sense, recognizing Nature as a subject of rights does not introduce a foreign element into the corpus iuris of the Inter-American system; rather, it represents a contemporary expression of the principle of interdependence between human rights and the environment” (para. 282).
Regarding the first part of this quotation, Article 29 of the ACHR establishes a criterion of normative integration according to which it must prevail either the provision of this or another international treaty, or of the domestic law that enhance the protection of human rights at stake. This maxim, embodied in the pro persona principle, does not impose the modification urbi et orbi of the ACHR by virtue of other treaties and pronouncements by its international supervisory bodies. Rather, it implies that the obligations applicable to a State party to the Convention must be weighed against other treaties ratified by that particular country and by its domestic legal system, with the rule or principle that maximizes the protection of human rights always being chosen. Of course, this exercise would not be necessary if a source outside the inter-American human rights system (IAHRS) established an international obligation of an erga omnes nature, which does not seem to be the case with the recognition of Nature as a subject of rights.
As for the second part of the cited paragraph, the advisory opinion does not clarify how the recognition of Nature as a subject of rights fits into the inter-American corpus iuris, especially when Article 1.2 of the ACHR establishes that: “For the purposes of this Convention, a person is every human being”. It is surprising that the IACtHR did not make a single mention of this provision or of AO-22/16 – “Entitlement of Legal Entities to hold rights under the Inter-American Human Rights System.” This advisory opinion ratified the reiterated position of both organs of the inter-American system, in the sense that the application of the American Convention is limited to the rights and freedoms of individuals, with indigenous territorial rights and trade union rights being the only two exceptions whose holders are indigenous peoples and trade unions, respectively, and not their members considered individually. If the goal of the Inter-American Court was to modify this jurisdictional rule—enshrined in Article 1.2 of the ACHR and reaffirmed in AO-22/16—it should at least have stated its validity.
In an analysis published in a recent issue of the Due Process of Law Foundation’s journal on the Rights of Nature, I argued that if the legal system of a State Party to the ACHR confers rights on an ecosystem on which the physical and cultural subsistence of an Indigenous people depends, that people should be able to exercise procedural and substantive claims to their biocultural rights before the IAHRS. Here is an example in which the recognition of the rights of nature in the domestic sphere would lead to the justiciability of certain rights protected in the American Convention, without trivializing the ratione personae jurisdiction of the organs of the IAHRS (Art. 1.2) and the requirement to demonstrate harm to one or more individuals entitled to reparations (Arts. 44 and 63.1)
The Jus Cogens Nature of the Obligation Not to Cause Irreversible Damage to the Climate and the Environment
Under the Vienna Convention on the Law of Treaties, a jus cogens norm is one accepted and recognized by the international community of States as non-derogable, and which can be modified only by a subsequent norm of general international law of the same character. In the absence of case law and statutory or customary rules conferring jus cogens status on the prohibition of causing irreversible damage to the climate and the environment, AO-32/25 resorts to a kind of syllogism that could be summarized in the following paragraph:
“[…] to consider anthropogenic behaviors with an irreversible impact on the vital balance of the planetary ecosystem as not imperatively prohibited by international law would, logically, undermine the conditions necessary sine qua non for the validity of fundamental human rights already protected by international law as norms of that higher hierarchy. Therefore, the obligation to preserve that balance must be interpreted as an imperative international duty (para. 290, emphasis added).
Contrary to the highlighted statement, what does constitute a jus cogens norm is the prohibition of certain behaviors, most of which are prohibited under international criminal law (e.g., genocide; crimes against humanity; torture and cruel, inhuman, or degrading treatment; slavery and human trafficking; racial discrimination and apartheid), which violate the core international human rights treaties. Under the criteria systematized by the UN International Law Commission (ILC) in its “draft conclusions on the identification and legal consequences of peremptory norms of general international law (ius cogens)”, it is the prohibition of these behaviors, and not the fundamental rights that may be violated by them, that constitute jus cogens norms.
Another inaccuracy in the advisory opinion is the reference to an international consensus, expressed in general rules derived from international environmental law, which, in the opinion of the majority of four judges of the IACtHR, makes the prohibition of irreversible environmental and climate damage jus cogens norms. This conclusion seems to be based on a conceptual confusion between obligations of an erga omnes nature and the imperative nature of the norms that enshrine them. In addressing this issue, the dissenting opinion of President Hernandez López clarifies that:
“the distinction between the two categories has been recognized by international doctrine and jurisprudence, with all jus cogens norms also being erga omnes, but not vice versa. In this context […] I am of the opinion that, in view of both categorizations, the obligation to prevent irreversible damage to the environment could be considered an erga omnes obligation” (para. 33 of the dissenting opinion of Judge Nancy Hernandez López).
This was precisely the position taken by the International Court of Justice (ICJ) in its advisory opinion on “Obligations of States with Regard to Climate Change,” published a few weeks after AO-32/25. Unanimously, its judges concluded that “the obligations of States relating to the protection of the climate system and other parts of the environment from anthropogenic emissions of greenhouse gases, in particular the obligation to prevent significant transboundary harm under customary international law, are obligations erga omnes” (para. 440), without the ICJ making any mention of the jus cogens nature of these obligations.
It should be recalled that, in deciding the Case of the Residents of La Oroya v. Peru in November 2023, the IACtHR had stated that “the international protection of the environment requires the progressive recognition of the prohibition of such conduct as a peremptory norm (ius cogens) that gains recognition by the international community as a whole as a norm that does not admit derogation” (para. 129).² As Judge Pérez Goldberg indicates in her dissenting opinion in AO-32/25, “it is difficult to understand how, for this same Court, an obligation that in November 2023 did not reach the level of a peremptory norm of general international law (ius cogens) because it did not have sufficient consensus, could have become such in the brief interval of just over a year” (p. 7 of Judge Pérez Goldberg’s dissent).
Final Considerations
Without ignoring the various contributions of AO-32/25 described in part 2 of this article, the criticism made here is based on the premise that genuine jurisprudential progress is conditioned by the rigor of the reasoning that supports it, especially when the issuing body lacks coercive mechanisms for compliance and enforceability. Conversely, an obligation arising from weak judicial reasoning is easily circumvented by its recipients, modified, or ignored by future compositions of the same court.
In a situation similar to that of AO-32/25, the IACtHR concluded, in the 2006 Case of La Cantuta v. Peru, that the obligation to investigate crimes against humanity is a jus cogens norm (para. 160). This is the only international precedent that goes beyond the prohibition of such crimes to include the duty to investigate them as a peremptory norm of international law. Recent judgments by the IACtHR itself have evaded this rule, limiting the classification of jus cogens to the prohibition of the aforementioned international crimes. By elevating the prohibition of irreversible environmental damage to the status of jus cogens, AO-32/25 departed from the more sober interpretations of the ICJ and the International Tribunal for the Law of the Sea in similar advisory opinions. Although this progressive stance could influence future judgements of other courts, we cannot rule out the risk that it may be another isolated vanguard ignored by subsequent compositions of the Inter-American Court itself.
Regarding the recognition of the rights of Nature, the lack of clarity in the advisory opinion, in addition to warranting dissent from three of its seven members, generates expectations that are as legitimate as they are uncertain for those who submit petitions and requests for protection measures in favor of ecosystems and their components. Until the IACHR and, eventually, the Inter-American Court decide a contentious case in favor of a river, mountain, or forest, the question will remain open as to whether the advisory opinion changed the personal jurisdiction of the aforementioned bodies or whether it is merely an obter dictum, without the intention or substance to allow natural entities to be victims of violations of the ACHR.
¹ Among the instruments and initiatives mentioned in AO-32/25, the following stand out: the 1982 World Charter for Nature; the Convention on Biological Diversity; the Kunming-Montreal Global Biodiversity Framework; and the Agreement on the Conservation and Sustainable Use of Marine Biological Diversity in Areas Beyond National Jurisdiction. The opinion also mentions the 2024 Pact for the Future; resolutions of the General Assembly and reports of the UN Secretary-General within the framework of the Harmony with Nature initiative which, in the words of the Inter-American Court itself, “evidence the growing recognition of the jurisprudence of the Earth and the rights of Nature worldwide”.
² On this occasion, Judges Ferrer Mac-Gregor, Mudrovitsch, and Pérez Manrique issued a minority opinion, stating that the international community had already recognized that the prohibition of irreversible environmental damage is jus cogens.
Image credit: via Freepik.com
Daniel Cerqueira