Key takeawaysKey takeaways

  • A prior legal publication alone is rarely sufficient to disqualify an arbitrator, but a specific publication closely tied to the exact issue and reinforced by other evidence, as in CC/Devas v. India, may justify disqualification.
  • Prior participation in another arbitration can support disqualification when there is identity or very close similarity in the applicable law, the relevant facts, and the parties or connected persons, as in Caratube v. Kazakhstan.
  • Public statements by an arbitrator with exact language revealing prejudgment of matters relevant to the case, such as in Perenco v. Ecuador, can sustain a challenge, while merely unfavourable procedural rulings are normally speculative.
  • Double-hatting becomes an issue conflict when an arbitrator's other professional role, such as acting as counsel on the same or closely related legal issue, gives the arbitrator a practical reason to favour a legal position, as in Telekom Malaysia v. Ghana.
  • Successful issue-conflict challenges require precise identification of the prejudged issue, contextual facts reinforcing each other, meaningful overlap between proceedings across law, facts, and parties, and reliance on the arbitrator's exact words, with IBA Guidelines serving only as guidance.


  • A prior legal publication alone is rarely sufficient to disqualify an arbitrator, but a specific publication closely tied to the exact issue and reinforced by other evidence, as in CC/Devas v. India, may justify disqualification.
  • Prior participation in another arbitration can support disqualification when there is identity or very close similarity in the applicable law, the relevant facts, and the parties or connected persons, as in Caratube v. Kazakhstan.
  • Public statements by an arbitrator with exact language revealing prejudgment of matters relevant to the case, such as in Perenco v. Ecuador, can sustain a challenge, while merely unfavourable procedural rulings are normally speculative.
  • Double-hatting becomes an issue conflict when an arbitrator's other professional role, such as acting as counsel on the same or closely related legal issue, gives the arbitrator a practical reason to favour a legal position, as in Telekom Malaysia v. Ghana.
  • Successful issue-conflict challenges require precise identification of the prejudged issue, contextual facts reinforcing each other, meaningful overlap between proceedings across law, facts, and parties, and reliance on the arbitrator's exact words, with IBA Guidelines serving only as guidance.

Arbitrators are often selected precisely because they know the field and have expressed views on difficult legal questions. Expertise, however, has a limit. A problem arises when a prior position is no longer simply an opinion, but creates a reasonable concern that the arbitrator will not approach a central issue with an open mind. This is the core of what is commonly described as an “issue conflict”.

Issue conflict is different from the conventional conflict of interest. The Key takeaways

  • A prior legal publication alone is rarely sufficient to disqualify an arbitrator, but a specific publication closely tied to the exact issue and reinforced by other evidence, as in CC/Devas v. India, may justify disqualification.
  • Prior participation in another arbitration can support disqualification when there is identity or very close similarity in the applicable law, the relevant facts, and the parties or connected persons, as in Caratube v. Kazakhstan.
  • Public statements by an arbitrator with exact language revealing prejudgment of matters relevant to the case, such as in Perenco v. Ecuador, can sustain a challenge, while merely unfavourable procedural rulings are normally speculative.
  • Double-hatting becomes an issue conflict when an arbitrator's other professional role, such as acting as counsel on the same or closely related legal issue, gives the arbitrator a practical reason to favour a legal position, as in Telekom Malaysia v. Ghana.
  • Successful issue-conflict challenges require precise identification of the prejudged issue, contextual facts reinforcing each other, meaningful overlap between proceedings across law, facts, and parties, and reliance on the arbitrator's exact words, with IBA Guidelines serving only as guidance.

concern is not necFAQ

What is an issue conflict in international arbitration?

An issue conflict is a form of impartiality or bias challenge where an arbitrator's prior position on a legal or factual issue creates a reasonable concern that they will not approach that central issue with an open mind, even without any financial, professional, or personal relationship with a party.

Can an arbitrator be disqualified just for having written about the legal issue in the case?

No, academic writing alone is rarely enough to justify disqualification, as seen in Saipem and Urbaser, but a specific publication closely tied to the exact issue and reinforced by other evidence, like in CC/Devas v. India, may carry considerably more weight.

When does an arbitrator's participation in a prior arbitration justify disqualification?

Prior participation justifies disqualification when there is identity or very close similarity in the applicable law, the relevant facts, and the parties or connected persons, as in Caratube v. Kazakhstan, where the arbitrator had sat in a case involving closely related persons and a substantially overlapping factual background.

What kind of public statements by an arbitrator can lead to a successful challenge?

Public statements with exact language that reveals prejudgment of matters relevant to the case, such as in Perenco v. Ecuador where Judge Charles Brower commented on Ecuador's conduct, can sustain a challenge, but merely unfavourable procedural rulings are normally speculative.

What is double-hatting and can it create an issue conflict?

Double-hatting is when an arbitrator simultaneously acts in another incompatible professional role, like as counsel on the same or closely related legal issue, and it becomes an issue conflict when that role gives the arbitrator a practical reason to favour a legal position, as in Telekom Malaysia v. Ghana, where Professor Emmanuel Gaillard had to choose between the roles.

essarily a financial, professional or personal relationship with a party. It is a possible predisposition toward a legal or factual issue that will have to be decided in the arbitration. In the taxonomy developed in the underlying thesis, issue conflict is therefore treated as a form of impartiality or bias challenge rather than a conventional independence challenge.

What Is an Issue Conflict?

Independence and impartiality are related, but they ask different questions. Independence normally concerns objective links between the arbitrator and a party, counsel or another participant. Impartiality concerns the arbitrator’s state of mind: whether the case can be heard without favouring a party, an outcome, or a particular position on an issue.

An issue conflict arises when the concern is directed at the issue itself. The arbitrator may have no relationship with either party and may still appear unable to reconsider a position already taken on a question that is central to the dispute. The relevant line is not between an arbitrator who has opinions and one who does not. Experienced arbitrators inevitably have opinions. The line is crossed when the circumstances suggest that the opinion has become fixed to the point that the parties cannot realistically expect an open-minded assessment of their arguments.

This explains why issue-conflict challenges are difficult. The very materials used to select an experienced arbitrator — publications, awards, conference statements and professional work — may later be relied upon as evidence of predisposition. Yet treating every prior view as disqualifying would make specialist arbitration unworkable.

Academic writing is one of the most obvious sources of an issue-conflict argument. It is also one of the weakest when relied upon alone. The case law discussed in the thesis shows a consistent reluctance to equate scholarship with prejudgment. In Saipem and Urbaser, challenges based on academic opinions were rejected. The underlying idea is straightforward: a lawyer does not lose the ability to hear argument merely because he or she has written on the subject.

Belokon v. Kyrgyz Republic illustrates the point. Professor Jan Paulsson was challenged on the basis of writings and earlier work concerning denial of justice. The challenge failed because the respondent did not identify a sufficiently specific legal issue that had allegedly been prejudged. General expertise in a field was not enough; indeed, it could just as easily demonstrate why the arbitrator had been selected in the first place.[3]

CC/Devas v. India reached a different result. Professor Francisco Orrego Vicuña had participated in several cases involving the same interpretative issue and later defended the same position in writing even after the relevant awards had been annulled. The decisive point was not the existence of an article or book chapter in isolation. It was the broader context: repeated decisions, the persistence of the view, and a later publication defending it. Taken together, those facts were capable of creating doubt as to whether further submissions could realistically change the arbitrator’s mind.[2]

The practical distinction is therefore between a prior opinion and evidence of a fixed position. A broad article on a legal doctrine will rarely be enough. A specific publication, closely tied to the exact issue in dispute and reinforced by other evidence, may carry considerably more weight.

Prior Awards and Similar Proceedings

The most common issue-conflict argument concerns an arbitrator’s participation in earlier proceedings where similar questions were decided. Again, repetition is not automatically suspicious. If the same legal rule is applied to similar facts, similar reasoning may simply reflect consistency rather than bias.

Caratube v. Kazakhstan is the clearest example in the thesis of a successful challenge based on prior participation. The challenged arbitrator had already sat in another arbitration against Kazakhstan involving closely related persons and a substantially overlapping factual background. The unchallenged arbitrators focused on the degree of familiarity between the two cases and on whether information acquired in the first case could matter in the second. The challenge was upheld.[4]

The thesis draws a useful practical test from this line of cases: look for identity or very close similarity in three areas — the applicable law, the relevant facts, and the parties or persons connected with them. No single factor is necessarily decisive. The stronger the overlap across all three, the more plausible the argument that the earlier case may have affected the arbitrator’s ability to examine the later dispute afresh.

Public Statements and Conduct in the Pending Case

Issue conflict may also arise from statements made during, or in connection with, the pending arbitration. Here the exact language and its context matter more than any abstract doctrine.

In Perenco v. Ecuador, the challenge to Judge Charles Brower followed a public interview in which he commented on Ecuador’s conduct and the dispute. The challenge was sustained. The decision, as analysed in the thesis, is important because it did not depend on a relationship between the arbitrator and a party. The problem was the appearance created by the arbitrator’s own words and the concern that they revealed prejudgment of matters relevant to the case.[5]

The opposite situation is a challenge based merely on an unfavourable procedural ruling. Such arguments are normally speculative. A party’s disagreement with document production, bifurcation, scheduling or another procedural decision does not by itself show that the tribunal has prejudged the merits. There must be something more: language or conduct that can reasonably be read as showing that a material issue has already been decided in the arbitrator’s mind.

Double-Hatting and Role Conflict

Issue conflict sometimes overlaps with “double-hatting”, although the two concepts should not be treated as identical. Double-hatting concerns incompatible professional roles. It becomes an issue conflict when the arbitrator is simultaneously acting in another capacity — most notably as counsel — on the same or a closely related legal issue.

Telekom Malaysia v. Ghana is the classic example. Professor Emmanuel Gaillard was acting as arbitrator while also serving as counsel in another arbitration involving a similar legal issue. The District Court of The Hague considered the tension between the role of counsel, who must advance the client’s position, and the role of arbitrator, who must remain open to both sides. The court treated the appearance created by those conflicting roles as sufficient to require a choice between them.[6]

A similar concern appeared in Blue Bank v. Venezuela, where the challenged arbitrator was a partner in a law firm representing an investor in another arbitration against Venezuela. The decision took into account the relationship between the firm’s offices and the similarity of the issues in the two proceedings. This type of challenge is stronger where the arbitrator’s other professional role gives him or her a practical reason to favour a legal position that may also matter in the arbitration being decided.[7]

What Usually Makes an Issue-Conflict Challenge Succeed?

The cases do not produce a mechanical test. They do, however, point to several recurring features.

1. Identify the issue precisely. A challenge framed at the level of “investment protection”, “denial of justice” or another broad field is unlikely to be persuasive. The alleged prejudgment should relate to a concrete legal or factual question that can affect the outcome.

2. Build context, not a collection of quotations. A publication, a prior award or a public statement is rarely decisive on its own. Successful challenges tend to rely on several facts that reinforce one another.

3. Show meaningful overlap between proceedings. Where the challenge relies on prior arbitral work, similarity of law alone is weak. Similarity of law, facts and parties or connected persons is much more significant.

4. Use the arbitrator’s exact words where conduct is relied upon. In public-statement cases, wording and context may be more important than labels such as “bias” or “prejudgment”.

5. Treat the IBA Guidelines as guidance, not a substitute for the facts. The thesis shows successful and unsuccessful challenges both with and without substantial reliance on the Guidelines. The ultimate question remains whether the circumstances create a sufficient appearance that the arbitrator may not approach the issue with an open mind.

Conclusion

An arbitrator is not required to be a blank slate. International arbitration depends on specialists, and specialists have published views, prior awards and professional histories. Issue conflict becomes serious only when those circumstances move beyond expertise and begin to show an inability — or a convincing appearance of inability — to reconsider a central issue on the basis of the parties’ submissions.

The case law considered in the thesis suggests that successful challenges are exceptional because they depend on context. Legal writings alone rarely suffice. Prior participation matters most when the disputes are unusually close. Public statements matter when their wording points to prejudgment. Double-hatting matters when a second professional role gives the arbitrator a stake in maintaining a legal position. Across these categories, the recurring question is the same: can the parties reasonably expect the arbitrator to hear the issue with an open mind?

References

[1] UNCITRAL Model Law on International Commercial Arbitration, Article 12; IBA Guidelines on Conflicts of Interest in International Arbitration (2014).

[2] CC/Devas (Mauritius) Ltd. et al. v. Republic of India, PCA Case No. 2013-09, Decision on the Respondent’s Challenge to Hon. Marc Lalonde and Prof. Francisco Orrego Vicuña, 30 September 2013.

[3] Valeri Belokon v. Kyrgyz Republic, PCA Case No. AA518, Decision on Challenges to Arbitrators Professor Kaj Hober and Professor Jan Paulsson, 6 October 2014.

[4] Caratube International Oil Company LLP and Devincci Salah Hourani v. Republic of Kazakhstan (II), ICSID Case No. ARB/13/13, Decision on the Proposal for Disqualification of Mr. Bruno Boesch, 20 March 2014.

[5] Perenco Ecuador Ltd. v. Republic of Ecuador and Empresa Estatal Petróleos del Ecuador, ICSID Case No. ARB/08/6, Decision on Challenge to Arbitrator, 8 December 2009.

[6] Telekom Malaysia Berhad v. Republic of Ghana, Decision of the District Court of The Hague Regarding Challenge to Arbitrator Gaillard, 18 October 2004.

[7] Blue Bank International & Trust (Barbados) Ltd. v. Bolivarian Republic of Venezuela, ICSID Case No. ARB/12/20, Decision on the Parties’ Proposals to Disqualify a Majority of the Tribunal, 12 November 2013.