Disqualification challenges against international investment arbitrators are increasing. This poses a great challenge for the legitimacy of the international investment regime. The aim of the Article is to trace the source of this development and to propose ways for the future structuring of an international investment regime that is both transparent and effective. Legal literature understands arbitrator independence as a standard imposed by legal rules. This does not capture the reality of international investment arbitration, especially in the framework of the ICSID Convention, which seems to set a lower standard of independence for ICSID arbitrators.

This Article presents the latest trends in the challenge process based on an empirical study of the most recent ICSID tribunal decisions. The thesis of the Article is that arbitral independence in international investment arbitration is the result of a “process of communication” among different actors and prompted by the arbitration community itself. Arbitral independence is only partially a result of legal rules. It is also a consequence of the creation of a tightly connected community of international arbitrators that has been established over the years of arbitral practice and which has transposed their ethos and professional practices onto investment arbitration. This community has constructed a very high standard of independence for international investment arbitration, which is now set in motion by other actors involved in the field. The Article proposes finally the introduction of a new system of control in international investment arbitration that can address the peculiarities of the constructed process of the creation

of investor-state arbitration: certification.