A question of impartiality: Who are the dissenting arbitrators in investment treaty arbitration?

As part of the larger debate on the legitimacy of the international investment regime, our study of 117 dissents and 87 dissenting arbitrators finds no significant correlation between the nationality of the dissenters, their gender, or appointment by the investor or the State, and the number of dissents written. In the absence of data on the educational and professional backgrounds of all appointed arbitrators, our findings concerning education and the professional background are more tentative. Where we do see significant correlation, is between dissents and appointments by the losing party. Arbitrators appointed by the losing party dissented roughly three times more often than the other arbitrators did. The fact that most dissents are written by arbitrators appointed by the losing party creates the perception that some arbitrators act more like the advocates of their appointers instead of impartial adjudicators. We propose that a standing, two-tier investment court that provides for non-renewable, long-term appointments and fixed salaries could remedy the perceived partiality of party-appointed arbitrators and ensure the survival of dissents.