The Independence and Impartiality of ICSID Arbitrators

Current Case Law, Alternative Approaches, and Improvement Suggestions


The legitimacy of investor-State arbitration is a much-debated topic, with arbitrators’ independence and impartiality being one of the core concerns. In The Independence and Impartiality of ICSID Arbitrators, Maria Nicole Cleis explores how unbiased decision-making is ensured under the ICSID Convention. Juxtaposing existing disqualification decisions in the ICSID system against corresponding requirements in related dispute settlement systems, the book convincingly argues that the current approach to disqualification requests against ICSID arbitrators is too exacting in light of the high stakes of investor-State disputes. The author’s nuanced analysis of the status quo is followed by novel suggestions for reforms (including a proposal for ICSID-specific guidelines on conflict of interest), making the book a valuable source of ideas on constructive paths forward.
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Maria Nicole Cleis, Ph.D. (2016, University of Basel), LL.M. (2014, Harvard Law School), Attorney-at-law, is a postdoctoral researcher at the University of Basel, and a lecturer in International Investment Law at the University of Neuchâtel.
List of Illustrations
List of Abbreviations

 Structure of the Book

1 Independence and Impartiality in the icsid Convention and Arbitration Rules
 1 Legal Framework and Drafting History
  1.1 The Requirement of Independence and Impartiality
  1.2 The Disqualification of Arbitrators
  1.3 Arbitrators’ Disclosure Obligation
 2 Delimiting Independence and Impartiality in a System of Party-appointments
  2.1 The Notions of Independence and Impartiality
  2.2 Party-appointments and Independence and Impartiality

2 Disqualification Decisions under the icsid Convention and Arbitration Rules
 1 Formally Inconsistent Interpretations of the Disqualification Threshold
  1.1 Requirement of Strict Proof under Amco Asia
  1.2 Requirement of Reasonable Doubts under Vivendi and sgs
  1.3 Inconsistency of the Disqualification Threshold in Subsequent Decisions
   A Challenge Decisions Applying the Amco Asia Standard
   B Challenge Decisions Applying the Vivendi Standard
   C Challenge Decisions Referring to Both Standards
  1.4 Conclusion
 2 Application of the Standard to Specific Categories of Alleged Conflict
  2.1 Behavior in Current Proceeding
  2.2 Familiarity with Another Participant in the Proceeding
   A Previous Contacts with a Party or Counsel
   B Role Switching between an Arbitrator and Counsel
   C Repeat Appointments
  2.3 Familiarity with the Subject-matter of the Proceeding
  2.4 Connection to an Adverse Third Party
  2.5 Conclusion
 3 Factors Underlying the Prevalent Dismissal of Arbitrator Challenges

3 Alternative Standards of Independence and Impartiality
 1 International Adjudication
  1.1 Relevance
  1.2 The International Court of Justice
   A Independence and Impartiality Requirements
   B Removal of icj Judges
   C Case Law
  1.3 Dispute Settlement in the World Trade Organization
   A Independence and Impartiality Requirements
   B Challenge of Panelists and Members of the Appellate Body
  1.4 Contextualization and Conclusion
 2 International Commercial Arbitration
  2.1 Relevance
  2.2 The uncitral Arbitration Rules
   A Behavior in Current Proceeding
   B Familiarity with Another Participant in the Proceeding
   C Familiarity with the Subject-Matter of the Proceeding
   D Connection to an Adverse Third Party
  2.3 The scc Arbitration Rules
   A Familiarity with Another Participant in the Proceeding
   B Familiarity with the Subject-Matter of the Proceeding
  2.4 The icc Arbitration Rules
   A Familiarity with Another Participant in the Proceeding
   B Familiarity with the Subject-Matter of the Proceeding
   C Connection to an Adverse Third Party
  2.5 Contextualization and Conclusion
 3 Self-regulatory Codes of Conduct for Arbitrators
  3.1 Relevance
  3.2 The iba Guidelines
   A General Standards
   B Application Lists
   C Case Law
  3.3 Contextualization and Conclusion
 4 Sui Generis Dispute Resolution Mechanisms
  4.1 Relevance
  4.2 The Iran–United States Claims Tribunal
  4.3 The Permanent Court of Arbitration
  4.4 Contextualization and Conclusion
 5 Summary Analysis
  5.1 Basic Consensus
  5.2 Prevalent Threshold
  5.3 Effect of the Threshold on the Outcome
   A Main Discrepancies
   B Main Similarities
   C Gaps in the Case Law

4 Analysis of Existing Reform Proposals
 1 Abolishment or Modification of the System of Party-appointments
  1.1 Appointment by a Neutral Body
  1.2 Party-appointment from a Roster
  2 Prohibition of Dual Functions
  2.1 Complete Prohibition
  2.2 Temporary Prohibition and Vesting Period
  2.3 Disinvolvement upon Challenge?
 3 Clarification of the Threshold for Arbitrator Challenges
  3.1 Excessive Rigor of the Strict Proof Threshold
  3.2 Adequacy of the Justifiable Doubts Threshold
 4 The Investment Court System Proposed by the European Union
  4.1 Investor-state Dispute Settlement under ceta
  4.2 Investor-state Dispute Settlement under ttip
  4.3  ics – Panacea or Chimera?

5 Improvement Suggestions
 1 Institutional Reforms
  1.1 Appointment of the Chairperson from a Roster
  1.2 Institutional Confirmation of Party-appointed Arbitrators
  1.3 Institutional Jurisdiction for Arbitrator Challenges
 2 Guidance on the Interpretation of a Justifiable Doubts Threshold
  2.1 Compulsory Grounds for Disqualification
  2.2 Potential Grounds for Disqualification
   A Reversal of the Burden of Proof
   B Burden of Proof on the Challenging Party
  2.3 No Grounds for Disqualification
  2.4 Proposal for icsid -specific Guidelines on Conflict of Interest
   A Incompatibilities
   B Potential Grounds for Disqualification
   C Unproblematic Circumstances
 3 Implementation of Suggested Reforms

Legal Sources
uncitral Cases
All interested in International Investment Law and investor-State arbitration in particular. Readership includes academics, lawyers and arbitrators involved in investment-related disputes (including in-house counsel), treaty negotiators and NGOs.