In Conversation with Mario Oyarzábal

Ambassador Oyarzábal, thank you very much for accepting this invitation from the Völkerrechtsblog, which will constitute part of our new series: The Person Behind the Practitioner.

I thank the Völkerrechtsblog and you, Antonio, in particular for the interest and the opportunity to share my perspectives and experiences in the field of international law.

While a significant part of our readership will be acquainted with your person and your career, it would be proper to frame this short interview by briefly reminding them of its most salient features. Mario Oyarzábal has been Argentina’s Ambassador to the Netherlands since 2020, a member of the International Law Commission (ILC), a member of the Institute of International Law,  a permanent representative for Argentina to the OPCW, a former legal adviser to the Argentine Foreign Ministry, and a former member of the PCA. He has an extensive legal and diplomatic career in the Argentine Foreign Service that has included appointments as legal counsel before the International Court of Justice. He has also published extensively on public international law and private international law, and is the author of 4 books and over 50 articles published in law journals and collective works.

Ambassador Oyarzábal, you have an extensive career in international law. You have served as counsel, arbitrator, professor, commissioner, and diplomat. In retrospect, which one of these experiences was the most critical for your development as an international lawyer?

The answer is all of them, as each experience has contributed to the development of my own perspective of international law, enhancing skills, and integrating them into my different roles and activities.

Nevertheless, if I had to choose one, I would say the position of legal adviser of the Foreign Ministry which I held between 2016 and 2020, a position that was both very challenging but also very formative and stimulating. The job of legal adviser –or at least how I approached it – is, on the one hand to be a lawyer for the State, hence the need to provide the President and the Foreign Minister with the legal tools to achieve national interests and their foreign policy objectives (whether you personally agree or not); and on the other hand to be the custodian of international law, which in Argentina is constitutionally part of the law of the land, and promote the rule of law at the international level more generally, which I fiercely believe is in the best interest of the international community and future generations as well as of my own country.

You have represented Argentina before the UNIDROIT, the UNCITRAL, and now you serve as a member of the ILC. Aside from the differences that stem from the subject matter of each institution and their mandate, is there any notable difference as to working methods that you would find consequential in these institutions?

There are indeed several differences due to the fact that they fulfill different functions (the ILC is charged with the progressive development and codification of public international law; UNCITRAL with developing international trade and investment law: and UNIDROIT with the unification of private law) and that they have different compositions (the ILC and UNCITRAL are subsidiary organs of the UN General Assembly, while UNIDROIT is an independent international organization; the members of UNCITRAL and UNIDROIT are States, while ILC members are individuals sitting in their individual capacity and not as representatives of their Governments) among other reasons.

That obviously impacts on the working methods. For example, neither the work of UNCITRAL or UNIDROIT needs to be rooted (theoretically at least) in State practice, unlike that of the ILC; and in the work of both UNCITRAL and UNIDROIT (more in the latter than in the former) civil society, including the business community and private experts, play a far greater role than in the ILC’s work.

On the other hand, all three are impacted by developments on the international plane, such as the move from hard-law to soft-law production.

As member of the International Law Commission you are currently part of various study groups, planning groups, working groups and drafting committees. Could you share with us a development  or an issue in which you currently focus your work on?

Participation in subsidiary organs of the ILC is optional but I have chosen to be in all of them. All issues are important, both procedural and substantive, for different reasons.

For example the evolution of the working methods of the Commission is decisive because of their impact on the substantive work; and the long-term program of work is important, not only to be able to take up new issues once one ends, but also as it allows the ILC to survey and reflect on problems and areas where it can make a contribution.

As far as substantive issues are concerned, the work in the drafting committees is of paramount importance, because they are the forums where ILC members debate openly and in great depth the issues at hand. They not only deal with drafting but are also where the direction of the work is decided (if only because of the lack of another forum in the majority of cases), where substantive issues are discussed and where possible solutions are envisaged. In turn, each drafting committee has its own dynamics which are related, in different degrees, to the reception by ILC members of the reports of the special rapporteurs, to the composition of the drafting committee (which tends to be larger for traditional cross-cutting topics and smaller for more specialised topics), and to how divisive and/or politically sensitive the question is.

For me, all topics in the ILC’s program of work or some aspects of them are important. For example, the topic of subsidiary means is important because of the need to “get it right” on issues such as the weight to be given to the decisions of judicial and extra judicial bodies; settlement of disputes to which international organizations are parties because of the impact it may have on access to justice for individuals and the immunities of such organizations; non-legally binding agreements for their practical utility for governments; sea-level rise due to the transcendental, existencial even, nature of the problem; and immunities of State officials from foreign criminal jurisdiction because of the role that the ILC can play in helping shape the law on an issue which is crucial for international relations.

The objects of the International Law Commission, according to the UN Charter (Article 13) and the Statute of the ILC (Article 1) are the promotion of the progressive development of international law and its codification. Occasionally the work of the Commission will acknowledge that a topic or a rule is not persistently evident in the behaviour of States and that a formulation would be part of that function of progressive development. On other occasions, however, a rule or a principle may be endorsed without such caveat. I would like to ask you how you approach this issue in practice and whether ambiguity is sometimes tacitly endorsed by the ILC to achieve the purpose of progressive development.

First, I would say that in my opinion progressive development should be the main objective of the ILC’s work, where it can provide more added value, because of the unique position the ILC holds as an organ of the most important universal organization that is the United Nations, its universal mandate, and the diversity of legal cultures and backgrounds that the ILC members represent.

Second, the ILC is not a legislative body and it should take great care not to assume a role that lies primarily with States. Given the weight of the ILC’s products in the formation of State practice, judicial proceedings and legal discourse, the risk is not negligible.

Hence, the need to clarify whether a proposition is a rule of law, a rule in the process of development, or a de lege ferenda proposition, remains crucial.

Third, sometimes differentiation between codification and progressive development is simply not possible because the state of the law on a certain issue is not settled as State practice and opinion iuris differ. In these cases ambiguity, besides being a way of achieving consensus within the ILC, constitutes a tool not so much to (positively or covertly) achieve the purpose of progressive development but rather to not impede (create an obstable to) such development.

At the moment of writing, international politics goes through considerable changes and crisis narratives abound in international law. What would you say is the role of the International Law Commission in the face of such changes or crises?

The ILC works in a political environment. The problem is that, if it acts politically, it loses its added value. More than ever, in times of crisis, the ILC should be faithful to its mandate, and perform its functions in a technical and independent manner.

During this time of political polarisation and conflicting narratives on international law, the ILC’s role in the identification of the State practice and opinion iuris of the different regions and across different legal systems becomes more important than ever.

Moreover, as the priorities of the international community change, the ILC must embrace topics that are commensurate with the times we are living in, including politically sensitive and specialised questions (without abandoning foundational or more traditional topics) to help enhance the coherence of the international legal system but also to remain relevant in terms of the interest of States and other stakeholders in its work.