Arbitrator challenges and the attendant effects on party autonomy have received increased attention in recent years. Challenges have been on the rise over the past decade, not only because the number of disputes submitted to arbitration has increased, but also because the parties, arbitrators and issues involved in international arbitrations have tended to recur in multiple proceedings, particularly in the context of investment disputes. As a result, the connections – or perceived connections – between the tribunal members, the parties and the issues in dispute have become increasingly complex. Concerned parties have relied on arbitrator challenges as a tool to ensure fairness in the arbitral proceedings by seeking to remove arbitrators who may lack the requisite independence or impartiality. Meanwhile, unscrupulous parties have sometimes seized on the challenge mechanism as a tool to delay or disrupt the proceedings, raising what have been termed “strategic” or “tactical” challenges.
Arbitrator challenges invoke equally important but potentially conflicting values that underpin the system of international arbitration. These are party autonomy, on the one hand, and adjudicatory fairness, on the other. The ability to appoint an arbitrator is a key manifestation of party autonomy, often credited with contributing to arbitration’s legitimacy and attractiveness as a method of international dispute resolution. At the same time, the right to be judged by an unbiased decision-maker is an essential principle of adjudication, as old as the law itself.