The ICJ should appoint experts in the advisory proceedings in
Obligations of States in respect of Climate Change
By Professor Eirik Bjorge, Dr Nilüfer Oral
Published on 4 December 2023
The year 2023 has been marked by an unprecedented number of requests for advisory opinions concerning climate change and State obligations under international law. This includes the request from the UN General Assembly to the International Court of Justice (ICJ) initiated by Vanuatu on Obligations of States in respect of Climate Change. Climate change represents a case par excellence where legal analysis needs to be informed by science. This was made abundantly clear during the oral proceedings of the Request for an Advisory Opinion submitted by the Commission of Small Island States on Climate Change and International Law before the International Tribunal for the Law of the Sea (ITLOS) in September 2023, where science was central to the submissions of the Commission of Small Island States on Climate Change and International Law (COSIS). However, this also presents a challenge given the large amount of scientific information available on climate change. Prominently placed among this information are the reports of the Intergovernmental Panel on Climate Change (IPCC). The UN Secretariat has already provided the ICJ with reports by the IPCC and others. The participants in the advisory proceedings will no doubt rely on yet more scientific reports; the total number of such reports may well run to several thousands of pages. The question is the extent to which these reports, which tend to be dense and highly technical, will assist the Court. An expert appointed by the Court itself could greatly facilitate navigating the complex field of climate science for the Court in Obligations of States in respect of Climate Change.
The Court may, pursuant to Article 50 of its Statute, ‘at any time, entrust any individual, body, bureau, commission, or other organization that it may select, with the task of carrying out an enquiry or giving an expert opinion’. As Gilbert Guillaume has pointed out, this provision is to the effect that the Court cannot take a ‘passive’ approach to evidence in cases before it (p. 97); it is encouraged to take an active approach. Nevertheless, it could be questioned whether the Court has adopted the active stance needed in order to deal effectively with complex fact- or science-intensive proceedings. Indeed, eminent commentators have posed the question whether the Court is equipped to understand and resolve scientific issues without the assistance of expert opinions. Some have wondered ‘whether a totally different approach is not required, namely, the establishment of and reliance on, in scientific matters, an expert appointed by the Court under Article 50 of the Statute’ (Higgins et al, p. 1240). It has also been observed that, in certain cases, the ‘preferable method for the ICJ to ensure that it acquires the required scientific or technical knowledge would be to appoint experts under Article 50’ (Gaja, p. 414). And Judges Al Khasawneh and Simma observed in Pulp Mills that ‘the Court, when handling a dispute with complex scientific or technical aspects (which will become all the more common as the world will be faced with more environmental or other challenges), should more readily avail itself of the tools available to it under its constitutive instrument in order properly to assess the evidence placed before it’ (Joint Dissenting Opinion, p. 12). We agree with these views and argue that the Court should make use of this power in Obligations of States in respect of Climate Change.
In a handful of contentious cases, the Court and its predecessor have had recourse to the power to appoint experts, whether to hold an enquiry or to give an opinion. These cases are: Factory at Chorzow (Claim for Indemnity), p. 51; Corfu Channel, pp. 20–21; Gulf of Maine, p. 265; Maritime Delimitation in the Caribbean Sea and the Pacific Ocean, Order of 31 May 2016, p. 237; and Armed Activities on the Territory of the Congo, Order of 8 September 2020, pp. 268–69.
The Court has, in other words, exercised the power in Article 50 only in relatively few cases. As more and more fact- and science-intensive cases are brought before it, however, there may be good reason for the Court to alter its stance—from passive to active. Indeed, if the Court has generally refrained from nominating its own experts, ‘[i]t is not certain … that the Court will be able to maintain this restrictive course in the future.’ (Kolb, p. 977). A passive attitude is also at odds with the practice of other dispute settlement bodies, which have been prepared to make use of external expertise (Tams & Devaney, p. 1434).
It emerges from the Court’s jurisprudence that the purpose of the expert opinion must be to ‘assist the Court in deciding upon the issues submitted to it for its decision’ (Application for Revision and Interpretation of the Judgment of 24 February 1982 in the Case concerning the Continental Shelf, p. 228). To this end, the power under Article 50 is necessarily flexible. It may be used so as to meet the requirements of the case before the Court in a particular proceeding. When it exercises its power under Article 50, therefore, ‘the Court enjoys some discretion in the designation and appointment of experts’ (Armed Activities on the Territory of the Congo, Order of 12 October 2020, p. 297). There is flexibility as to the timing of the determination as well (Application for Revision and Interpretation of the Judgment of 24 February 1982 in the Case concerning the Continental Shelf, pp. 227–28). It will be for the Court to ascertain the respective fields of expertise which it finds relevant to the task of providing it with assistance, and by extension also for the Court to satisfy itself of the relevance of the professional qualifications of the individuals to be appointed (Armed Activities on the Territory of the Congo, Order of 12 October 2020, p. 297). It will be ‘for the Court to determine what weight, if any, to be given to the assessments contained in the expert report’ (ibidem).
It is true, as Judge Sebutinde has observed, that the Court has appointed experts ‘only in “complex cases” requiring technical, scientific or specialized knowledge or expertise that is outside the realm of normal judicial expertise’ (Separate Opinion, Order of 8 September 2020, p. 285). In her view, ‘expert opinion must be limited only to those complex issues requiring technical, scientific or specialized knowledge or expertise that is outside the realm of normal judicial expertise’ (ibidem). We strongly agree.
But is this procedure available to the Court in advisory proceedings? It is. Article 68 provides that ‘[i]n the exercise of its advisory functions the Court shall further be guided by the provisions of the present Statute which apply in contentious cases to the extent to which it recognizes them to be applicable.’ Thirlway wisely remarked that the extent to which the Court is to be guided, in advisory proceedings, by the provisions of the Statute applicable in contentious cases ‘is perhaps particularly marked where the subject-matter of the request involves considerations of fact’ (p. 115). The Permanent Court accordingly recognized the provision in Article 50 to be applicable in the exercise of its advisory functions. It decided, for example, in Competence of the International Labour Organization to Regulate, Incidentally, the Personal Work of the Employer that certain experts produced by the International Federation of Trades Unions were not to be treated as witnesses, but that ‘they should be invited to reply to questions put by the representatives of international organizations and, if necessary, by the Court’ (P.C.I.J. Annual Report, Series E, 1926–27, pp. 212–13). Space precludes discussing further examples (see e.g. Sandifer, Evidence before International Tribunals (2nd edn, 1975) pp. 332–33).
Eminent commentators have also taken the view that Article 50 is applicable in advisory proceedings. Murphy has concluded that the procedure in Article 50 is an avenue open to the Court in advisory proceedings and has strongly encouraged its use (pp. 73–74). White was of the same view. She was able to add, with the clarity and prescience that characterize her writings, that ‘[i]t may be that some future request for an Advisory Opinion will involve the Court in appraising non-legal information to such a degree that it will consider it necessary to use its powers under article 50’ (G. White, “The Use of Experts by the International Court of Justice” in Fifty Years of the International Court of Justice (1996) p. 540). It is difficult to conceive of a request for an advisory opinion better suited than Obligations of States in respect of Climate Change for a determination by the Court that it would indeed be assisted by entrusting to an individual, body, bureau, commission, or other organization the duty of giving an expert opinion.
In the past the Court has tended to appoint individuals as experts. When Article 50 was originally drafted, the initial wording had only ‘any individual’. The words ‘body, bureau, commission, or other organization’ were then added so as to make it evident that, in addition to individuals, any organ of the Court’s choice could be so designated (Stauffenberg, Statut et règlement de la Cour permanente de Justice internationale (1934) p. 377).
The Court has in some cases appointed a handful of experts: three in Corfu Channel (where the experts formed a committee) and four in Armed Activities on the Territory of the Congo (where they acted individually). Appointing a group of experts appears to be a good model, whether the Court were to appoint individuals or entities, or an admixture thereof, and whether or not they would form a committee or act individually. Whatever the approach adopted, the IPCC, the UN body for assessing the science related to climate change (along with individual scientists who have led its work), would seem a very good candidate. Two eminent scientific experts, Dr Sarah Cooley and Dr Shobna Maharaj, who had played leading roles in the work of the IPCC, made clear and helpful presentations in the proceedings before ITLOS, to which many of the participants referred.
In Armed Activities on the Territory of the Congo the Court successfully appointed experts, who by reason of their particular individual expertise complemented one another and ably assisted the Court in addressing the issues before it. In that spirit, and given the questions the General Assembly has asked of the Court in Obligations of States in respect of Climate Change, the Court could also look to other bodies (and their leading individual scientists), such as: the World Meteorological Organization (WMO), the specialized agency of the UN for meteorology (weather and climate), operational hydrology, and related geophysical sciences; the World Health Organization (WHO), the specialized agency for the promotion of health; and the Food and Agricultural Organization (FAO), the specialized agency leading efforts to defeat hunger.
As Article 65, paragraph 2, of the Statute indicates, the Court should ideally be seised only of information that is ‘likely to throw light upon the question’ asked of it in an advisory proceeding. That provision reflects a broader point: it is not the case that more information— especially if it runs to several thousands of pages—will necessarily be tantamount to more light being shed upon the question. Instead, a surfeit of information could well mean that the information actually ‘likely to throw light upon the question’ is crowded out by less pertinent information. As Judge Yusuf has observed, particularly in cases ‘concerning the protection of the environment and the prevention of pollution, specialized scientific expertise can provide the Court with the insight necessary to make a thorough appraisal of the merits of the scientific and technical material submitted’ to it (Declaration, Pulp Mills, p. 217). There is, in this regard, every reason to believe that scientific expertise, duly appointed under Article 50, could assist the Court greatly in Obligations of States in respect of Climate Change. In these advisory proceedings, therefore, the Court would be well advised to take an active, not a passive, approach to the scientific evidence before it.
Professor Eirik Bjorge is a Professor at Bristol University Law School and an Adjunct Professor at Columbia Law School. He acted as counsel to Nauru in the climate change proceedings before ITLOS.
Dr Nilüfer Oral is the Director of the Centre for International Law of the National University of Singapore and Co-Chair of the International Law Commission. She acted as counsel to COSIS in the climate change proceedings before ITLOS.