So far, requests for advisory opinions have been only submitted to the ITLOS and the IACtHR. They are currently awaiting the courts’ response. A UN General Assembly’s vote to submit similar questions to the ICJ is also pending. This unusual synchronism has sparked some debate, not least because none of these international courts has meaningfully engaged with climate emergency concerns in their contentious or advisory functions. Asking different international legal authorities about one kind of planetary crisis could trigger either a global legal cacophony with accompanying contradictions or a new, complementary and helpful approach.
Even though all of these initiatives seek to discern legal questions in the context of the climate emergency, each court’s answer will vary based on several factors. These may include the question itself and some particularities shaped by their mandate, the breadth of their legal interpretation, the treatment of their information sources, and the socio-political context in which courts operate. The ITLOS and the IACtHR will mainly assess the legal obligations enshrined in the treaties that legitimise them. For instance, the question formulated for the ITLOS is primarily based on the Convention on the Law of the Sea, whose focus is the marine environment. In contrast, the IACtHR will mainly assess the American Convention on Human Rights, whose jurisdictional scope is not limited to a particular natural environment but rather the effects that State Parties have on human rights. In that sense, the IACtHR has already developed a rich environmental case law in contexts where resource extraction hampers indigenous peoples’ collective rights to property and dignified life.
The IACtHR’s expansive interpretation of civil and political rights, generated through a relational process of understanding the socio-ecological context of subaltern actors, already marks a different scenario vis-à-vis this court’s counterparts. The IACtHR’s approach in interpreting the content of a right in light of the facts tends to favour the victim’s interests instead 99 acres database those of the state. This sensibility influences how to delineate obligations to protect the climate system, which means it matters who benefits from such protection and where States should prioritise it. As argued elsewhere, the progressive normative production of the IACtHR is not a spontaneous phenomenon that emerges in a vacuum but instead is the outcome of a dialectical process in which the situated experience of victims shapes the IACtHR’s judicial interpretation.
The IACtHR tends to connect different international law regimes to create a maximalist pro-homine rationale, which may differ from the approach of the ICJ. The draft resolution for an advisory opinion to the ICJ, which Vanuatu has made public, contains two questions formulated with a list of international legal sources, including human rights and environmental treaties, that the ICJ must assess to answer. One can expect the ICJ to consider the treaties referred to in the request. However, past ICJ advisory opinions can inform us about the relevant law it uses to scrutinise a question: depending on the subject matter, it tends to rely on lex specialis or delegates the intricate details of ancillary law to another law-making body.
In Threat or Use of Legal Weapons, for example, the ICJ recognised that human rights law applies during times of war. Still, the applicable law used to exert a juristic examination was jus ad bellum, jus in bello, and specific treaties on nuclear weapons, thereby circumventing the opportunity to provide further clarification on other relevant legal regimes. In Separation of the Chagos Archipelago, when referring to the legal consequences of an unlawful process of decolonisation, the ICJ mentioned that international human rights law is applicable to assess the resettlement of Chagossians. Still, it is the General Assembly that should address it during the completion of the decolonisation of Mauritius. The applicable law selection suggests that the ICJ advisory opinion could deem the climate regime’s treaties as lex specialis, thereby passing the answer back to the climate negotiations and avoiding clarifying international obligations, as posed by Vanuatu’s question.