• Tutoriel vidéo


Mme Gabriela del Carmen Alcántara Torres

International dispute settlement lawyer

See all

Disqualification of Expert Witness

I. Definition


A legal impediment or privilege under the applicable legal or ethical rules, or for matters of procedural economy, proportionality, justice, or equality between the parties, may lead to a party’s request to remove its counterparty’s expert witness from the proceedings. Generally, parties do not contest the tribunal’s jurisdiction to decide on this matter.1 In practice, requesting the disqualification of an expert witness is uncommon.

II. Legal framework

A. Arbitration rules


The ICSID Convention does not expressly provide for the disqualification of expert witnesses. However, Article 44 grants the arbitral tribunal power to decide on any procedural question not covered in the Convention or the Arbitration Rules.2 Parties and tribunals have based the competence to decide on these requests on Rules 19 and 34(1) of the Arbitration Rules.3


Similarly, Article 29(2) of the UNCITRAL Arbitration Rules (2013), would grant tribunals the authority to decide on those objections.

B. IBA Rules on the Taking of Evidence in International Arbitration


The IBA Rules on the Taking of Evidence in International Arbitration have no specific provision on the disqualification of expert witnesses either. However, there are certain elements of independence that, when not complied with, have taken parties to present such an application, particularly those in Article 5(2)(a) and (c).4 To base the competence of tribunals to exclude evidence, parties have relied on Article 9(2)(b) and (g).5

C. Issues for Arbitrators to Consider Regarding Experts of the ICC


The document on “Issues for Arbitrators to Consider Regarding Experts,” prepared by the ICC, has also been referred to by the parties to request the disqualification of an expert witness.6

III. Grounds for an application of disqualification


There is no rule to determine the standard to disqualify an expert. The lack of independence, and even an employment relationship or a professional interest, might not be a reason to do so.7 (See Conflicts of Interest particularly in the case of party-appointed experts). Access to confidential and privileged information,8 not disclosing having had access to this information,9 failure to disclose professional relationships,10 bias,11 lack of qualifications,12 lack of independence,13 and impartiality14 have been raised as grounds to disqualify an expert. The threshold to be met on each ground is yet unclear. In the case of a challenge on bias, it has been considered that an appearance is not enough, but rather an actual bias is necessary.15

IV. Procedure


When a party in an arbitration considers that the expert witness of its counterparty is not complying with its obligations, it can present an application to the tribunal to disqualify such expert. There is no timeline or procedure to do this. In practice, it has been done as soon as practicable through a written communication to the tribunal16 or during the hearing.17 This issue has been decided as a ruling on that specific matter18 or along with the final award.19 Once the report has been duly presented, the burden of proof falls on the party requesting the dismissal of the expert.20

V. Standard to disqualify an expert witness


Since most arbitration rules grant tribunals the discretion to assess and weigh the evidence presented by the parties,21 the threshold to disqualify party-appointed experts is considered to be higher than that of an arbitrator (see Disqualification of Arbitrator). Some tribunals have even considered the disqualification of an expert witness to be a disproportionate measure.22 Tribunal-appointed experts seem to be bound by the same rules as arbitrators.23 Although there are no successful disqualifications of expert witnesses in the public record, tribunals have opted to consider the arguments in the application for disqualification during the decision phase to weigh the value of the experts’ reports.24 They have also suggested to the party whose expert is requested to be removed to appoint a different one instead.25


Sélectionner un mot clé :
1 /

Accédez instantanément à la jurisprudence, aux traités et à la doctrine les plus pertinents.

Commencez votre période d'essai

Déjà enregistré ?