THE AUTHOR:
Liana H. Cercel, International Lawyer, Independent Counsel at Brigantia Law
International arbitration occupies a complex position within transnational adjudication. It is not merely that arbitration contributes to the interpretation and development of public international law; the relationship also operates in reverse. Public international law, international courts and the habits of international judges have shaped arbitral jurisprudence. This reciprocal influence – described during the discussion as “cross-pollination” – was at the centre of the 8th Sciences Po – Mayer Brown lecture.
The event opened with introductory remarks by the event’s two founders, Dany Khayat (Partner and Head of International Arbitration and Litigation at Mayer Brown) and Professor Diego P. Fernández Arroyo (Director of the LL.M. in Transnational Arbitration & Dispute Settlement of Sciences Po Law School, President of the Curatorium of the Hague Academy of International Law, President of the International Academy of Arbitration Law and renowned arbitrator, amongst many other distinctions). Their remarks situated the discussion within transnational adjudication: not simply as an abstract theory of justice, but as a professional and institutional reality in which judges, arbitrators, arbitrator-judges and judge-arbitrators operate across overlapping legal spaces.
The debate was moderated by Isabella Lacreta (Partner at Mayer Brown), who actively engaged the audience on the central question of cross-pollination between judicial and arbitral functions. The audience response appeared to reveal a certain scepticism toward cross-pollination as a general proposition. Among those prepared to accept some movement between roles, there seemed to be greater comfort with arbitrator-judges than with judge-arbitrators – perhaps, as an authorial observation, because this direction of movement appears less likely to disturb the perceived virtuousness of ICJ judges.
The debate also featured contributions from Julien Fouret (Partner and Global Co-Head of HFW’s international arbitration practice), Jennifer Younan (Partner at Allen & Overy), Eliseo Castineira (Partner and Founder of Castineira Law), and Philippe Cavalieros (Partner and Global Head of Simmons & Simmons LLP’s international arbitration practice).
The keynote presentation was delivered by Professor Makane Moïse Mbengue (Professor at the University of Geneva and Sciences Po Paris, Director of the Department of International Law and International Organization of the University of Geneva and President of the African Society of International Law, amongst many other distinctions), under the title “Judges, Arbitrators and Judges-Arbitrators: Virtues and Constraints of Transnational Justice.” At the core of his presentation was the concept of the transnational adjudicating community: a community composed of those who decide disputes across domestic courts, international courts and arbitral tribunals.
This concept captures a defining feature of contemporary dispute resolution. International adjudication is no longer divided into sealed compartments. Legal reasoning, procedural techniques, reputations and ethical concerns all circulate, and they do so globally now more than ever. The question is not only whether judges and arbitrators influence one another, but whether such influence is beneficial, dangerous, or both.
Professor Mbengue’s keynote raised three core questions:
- Is there a functional frontier between international judges and arbitrators?
- Is there an axiological frontier between them?
- Can the judge-arbitrator (and/or the arbitrator-judge, seemingly preferred) serve as a vehicle for the cross-pollination of virtues and constraints within the transnational adjudicating community?
The keynote also showed that criticism directed at arbitration often seems to assume that judges and arbitrators occupy fundamentally different moral and institutional positions. Judges are frequently perceived as constrained, public, neutral and virtuous actors. Arbitrators, by contrast, are scrutinised through the vocabulary of bias, conflicts of interest, double-hatting, repeated appointments, self-promotion, cognitive deficiencies and professional incentives. The discussion challenged whether that contrast is as convincing as it is commonly assumed to be.
Criticism of investor-State arbitration and intra-EU investment arbitration has intensified these concerns. Arbitrators are often portrayed as a small professional community, repeatedly appointed and potentially affected by issue conflicts or cognitive bias. These criticisms raise serious questions about independence, impartiality and legitimacy.
Yet the keynote also exposed a possible asymmetry in how these concerns are applied. Practices treated with suspicion in arbitration may appear in comparable forms within international courts, without attracting the same level of reproach. Arbitrators may be criticised for self-promotion, while international judges operate within political and sometimes campaign-driven appointment processes. Arbitrators may be accused of politicising adjudication, while the composition of international courts, including the ICJ, is inseparable from State nomination, election and diplomatic support.
This does not mean that criticisms of arbitration are unfounded. It suggests that the comparison between judges and arbitrators is often insufficiently disciplined. If the argument is that they are different, the basis of that difference must be identified with precision: appointment processes, remuneration structures, institutional constraints, party relationships, contribution to precedent, public function, or inherited assumptions about public virtue and private service.
The distinction matters because it (should) determine(s) how the risks should be regulated. If judging and arbitrating are functionally different, different standards may be justified. If they are not fundamentally different, or if they increasingly overlap, differential treatment becomes harder to defend. The conference therefore raised a difficult question: is the judge-arbitrator problematic because the two functions are incompatible, or because the legal community has not developed coherent standards for managing their interaction?
The issue of cognitive bias was particularly important. If judging and arbitrating require distinct modes of reasoning, movement between the two roles may create risks of maladaptation. A judge sitting as an arbitrator may bring assumptions of public adjudication into a party-driven procedure. An arbitrator sitting as a judge may bring an arbitration-style procedural pragmatism into a permanent judicial institution. Yet if the two functions are not as different as critics suggest, these concerns may be overstated. The premise of cross-pollination is that some transfer of methods and sensibilities is not only inevitable, but potentially beneficial.
The harder question is how different the two systems really are. Courts are associated with stability, predictability, coherence and institutional maintenance. Arbitration is associated with expertise, flexibility, party confidence and procedural adaptability. But these categories should not be idealised. Courts are not immune from politics, strategic behaviour or institutional self-preservation. Arbitration is not necessarily devoid of legal discipline, public function or normative contribution. Both systems contain virtues and vulnerabilities.
The historical section of Professor Mbengue’s keynote reinforced this point. Returning to the Hague Peace Conferences of 1899 and 1907 and to the elaboration of the Statute of the Permanent Court of International Justice in 1920, the presentation showed that the tension between judges and arbitrators is not new. Actually, it has long structured international dispute settlement, and even arguably in a beneficial way (an example was given in this regard of the ICJ’s 1953 Nottebohm judgment which recognised the positive influence of the arbitrator-judge). Some historical figures favoured separability; others defended complementarity. The contemporary debate renews an old dilemma: whether international law is better served by separation or controlled movement between the judicial and arbitral functions.
The example of Max Huber was especially significant. His arbitral work (famously exemplified by the Island of Palmas award and the British Claims in the Spanish Zone of Morocco) illustrates how arbitral reasoning can travel into the broader fabric of international adjudication, later resonating in ICJ jurisprudence on territorial sovereignty, effectivités, intertemporal law and State responsibility. His example seems to contradict any rigid separation between arbitral and judicial functions, showing that international law has often developed through circulation between awards and judgments.
This perspective is directly relevant to the contemporary debate on ICJ judges sitting as arbitrators. The 2020 restrictions adopted by the International Court of Justice marked a significant shift away from what had previously been a relatively common practice. The question was not whether independence and impartiality matter; they plainly do. The more difficult question was whether moving from accepted practice to restrictive prohibition was the most appropriate response.
A bright-line prohibition has clear advantages. It protects the Court from reputational risk, avoids difficult case-by-case assessments and reinforces the appearance of judicial independence. But it also has costs. It limits the participation of ICJ judges where their expertise may be valuable, reduces opportunities for cross-pollination, and may suggest that legitimacy can only be preserved through separation rather than carefully designed ethical boundaries.
A point of broad convergence appeared to emerge from the discussion: the objective should not be to suppress cross-pollination altogether, but to discipline and channel it. Historically, cross-pollination has contributed both to the development of international adjudication and to the evolution of international arbitration. The more constructive task is to identify when movement between courts and arbitral tribunals can generate legal value without undermining independence, impartiality or institutional confidence.
This does not mean that every arbitral award or international judgment contributes to the formation of international law, nor that professional circulation should be accepted uncritically. The risks remain real: conflicts of interest, cognitive bias, self-promotion, repeat appointments and institutional capture cannot be ignored. But those risks do not necessarily justify closing the channels through which legal reasoning circulates. They justify regulating those channels more carefully.
The more persuasive approach may lie in principled regulation rather than categorical exclusion. Certain situations clearly raise bias risks: party appointments by States appearing before the same judge, overlapping issues creating structural conflicts, repeated appointments giving rise to economic dependence, or circumstances undermining confidence in impartiality. Other forms of movement may enrich transnational adjudication rather than threaten it.
This is where the criticism of arbitration requires nuance. It is not enough to say that arbitration is private and courts are public, and that the two should therefore be treated differently. That distinction is important, but not always conclusive. Investment arbitration, inter-State arbitration and other forms of international arbitration often decide questions with public consequences. Conversely, international courts operate in political environments and are not insulated from institutional incentives. The public/private divide cannot carry the full analytical burden.
The debate also raised a practical point: the distinctiveness of arbitration is not incidental to the system, but may be part of what its users seek. Parties who choose arbitration are often paying for a different form of dispute resolution – one capable of accommodating document-heavy proceedings, technical expertise, procedural flexibility, specialised decision-makers and rules adapted to the needs of a particular dispute. Arbitration is not defective simply because it departs from ordinary court adjudication. Its value lies in offering an alternative, flexible, privately managed means of achieving justice – provided that what it delivers can still properly be called justice.
The broader lesson of the discussion seemed to be that the transnational adjudicating community should not be understood through idealised contrasts. Judges are not necessarily more virtuous because they sit on courts, just as arbitrators are not necessarily less ethical because they operate in a party-appointed or fee-based system. The central issue appeared not to be whether judges and arbitrators are identical, nor whether they must be kept wholly separate, but whether the legal community can articulate a convincing account of their similarities and differences. Any differential treatment should be justified by function, structure and risk, not by inherited assumptions about virtue. The transnational adjudicating community already exists; the task, it seems, is to govern it with intellectual honesty, ethical consistency and institutional precision, by asking what constraints apply, what incentives are created, what risks arise and what safeguards can preserve confidence in the decision-making process.
In this author’s view, two further reflections arise from the discussion, although they go beyond the points expressly developed by the keynote and the debate.
The first concerns the role of enforceability and compliance in assessing arbitral legitimacy. Arbitration is often defended because it produces decisions capable of travelling across borders and generating practical consequences. An enforceable award that is complied with, whether voluntarily or through execution, and that results in recovery for the successful party offers a form of concrete relief that should not be dismissed. Effectiveness is part of arbitration’s claim to legitimacy. Yet effectiveness is not a complete answer to the ethical critique. An enforceable award is not necessarily a just award. Compliance may show that the mechanism worked, but not that the process was independent, impartial or substantively sound. The challenge is therefore to evaluate arbitration through both lenses: justice and effectiveness.
The second concerns the possible role of the transnational adjudicating community in the identification of general principles of law. Article 38(1)(c) of the ICJ Statute refers, in its dated formulation, to “the general principles of law recognized by civilized nations.” This source of international law is frequently treated as residual or underdeveloped. Yet transnational adjudication may provide one of the most fertile environments for its renewal. Because it brings together adjudicators from different legal traditions, nationalities, institutional cultures and areas of specialisation, the transnational adjudicating community may be uniquely positioned to reveal principles that travel across systems.
On this view, cross-pollination should not be seen only as a risk to be contained. It may also be a method of legal formation. The encounter between judicial and arbitral reasoning can operate as a filter: testing whether a principle is sufficiently portable, coherent and normatively persuasive to operate beyond one domestic system or one treaty regime. Properly channelled, this community may do more than resolve disputes. It may contribute to the identification of general principles of law and, in doing so, to the development of international law itself.
*This article reflects solely the author’s personal impressions and understandings as an attendee and participant of the related event. Nothing in it should be interpreted as expressing, representing, or attributing any view, position, or legal opinion to the keynote speaker, the debate participants, the organisers, or any of their respective firms, institutions, or professional affiliations.
ABOUT THE AUTHOR
Liana Cercel is an international lawyer admitted to the New York and Bucharest Bars, practicing as an Independent Counsel within the Brigantia Law network and part of the faculty of her alma mater, the LL.M. in Transnational Arbitration and Dispute Settlement program at Sciences Po Law School, Paris.
*The author is grateful to Mr. Daniil Turturoiu for his invaluable assistance, thoughtful contributions, and support in the drafting of this article. Mr. Turturoiu is a jurist, graduate of Université Paris Nanterre, and holder of a Master’s degree in International and European Business Law from Université Paris 1 Panthéon-Sorbonne.
*The views and opinions expressed by authors are theirs and do not necessarily reflect those of their organizations, employers, or Daily Jus, Jus Mundi, or Jus Connect.
