Chris Hilson
Professor of Law, University of Reading School of Law, Director of the Reading Centre for Climate and Justice
The Inter-American Court of Human Rights (IACtHR) enjoys a broad advisory jurisdiction under Article 64 of the American Convention on Human Rights. Its advisory opinions are meant to do just that – provide advice on the human rights obligations of Organization of American States (OAS) states and organs. The Court (in Advisory Opinion OC-32/25) has recently exercised this jurisdiction in relation to the human rights obligations related to climate change, producing an extensive Opinion on the matter.
The word ‘extensive’ is key to what follows. Advisory opinions are in the business of providing advice. For whom is that advice meant? Those who requested the Opinion (i.e. Chile and Argentina)? All OAS states? All states globally? Civil society? In their request, Chile and Argentina wrote that an opinion “will provide both the requesting countries and the other countries of the region with guidelines.” That no doubt represents the position as a matter of law. But we know that in practice the Opinion was anticipated and received globally, not only by states but by civil society groups and others. Many blog posts have already assessed the substantive content of the Opinion. Here I am less concerned with those individual elements than with what the Opinion’s overall message is: how does it ‘land’ as advice, and what are people globally likely to take away from it?
What is good or useful advice? The answer is probably, ‘it depends’. The provision of advice lies on a spectrum. At one end is what one might term a ‘kitchen sink’ approach, which is completist and tries to cover every possible base. Is this useful? The risk is that advice at this end of the spectrum will turn out to be a ‘nothing burger’ (defined by the OED as ‘something which, contrary to expectations, turns out to be insignificant or unremarkable’). Why? This is where the ‘it depends’ point comes in. Advice can be complete or it can be memorable, but it can seldom be both things at the same time. If you want advice to be memorable, then you generally need to make one or two points and make them clearly. That’s comms lesson 1.01.
Recent contentious as opposed to advisory jurisdiction cases have produced memorable rulings in a climate human rights context – the obvious example that springs to mind being the European Court of Human Rights KlimaSeniorinnen case. That is clearly identifiable as a case about climate targets and what human rights obligations require states to do on them.
What then of the recent IACtHR’s climate Opinion? The answer is that it veers much more towards the kitchen sink end of the spectrum rather than the selective end. If we look at the Opinion, it raises a truly extensive range of issues including the nature of the climate emergency, the status of IPCC reports, jus cogens, the right to a healthy environment and to a healthy climate, rights of nature, procedural rights, sustainable development, climate mobility, and standards of due diligence. Of course much of that reflects the extensive set of questions that were in Chile and Argentina’s original request, even with some reformulation and regrouping of them by the Court. But, has that nevertheless produced a nothing burger?
That would be unfair. It is an impressively wide-ranging Opinion and bold with it. There is a lot of meaningful filling inside the bun. But in terms of messaging and memorability, and advice in those terms, it is hard to know which of the many parts people will in the end fasten on when they say what the Opinion is ‘about’. Because, unlike say KlimaSeniorinnen, it is about so much.
It is, however, worth coming back to the ‘it depends’ point, because another thing it depends on is the audience. In terms of media messaging to the global public, it didn’t convey a core memorable point to galvanise opinion. But government international lawyers in OAS states can be expected to get their teeth into the kitchen sink immediately and indeed will probably relish doing so. They may accept some of the advice and resist other parts. For other audiences, the advice provided in instances like these (and the ICJ one is likely to be no different) is there to be drawn upon in the future. That includes of course courts, both international and domestic, but also civil society groups operating in the climate and human rights space. For those actors, the advice here should therefore be seen more like off-the-peg or ready-to-wear garments of many types, which can be taken off the racks and used by them. Some will be attracted to and choose one outfit (the sustainable development one perhaps) rather than another (like rights of nature) depending on local fit. Whether the garments are all of the same quality is something lawyers will no doubt be debating for some time. Contentious jurisdiction judgments, in contrast, are more like bespoke or made-to-measure clothing.
In the end then, while in one sense the recent IACtHR’s climate Opinion does take a kitchen sink approach, the more appropriate metaphor might be of an extensive or commodious walk-in-wardrobe or closet. But a nothing burger it is not.