Indeed, such legal opinions may be of limited
relevance in commercial arbitration, which normally concerns the application
of domestic legal norms as specified in the parties’ contract. By contrast,
arbitrators in investment arbitration frequently deal with repeating issues of
international law, and are often asked to determine rules as a matter of fi rst
impression. On this basis, predisposition with respect to a particular question
of law, even if expressed in general terms, could give rise to justifi able doubts
as to the author’s receptiveness to certain arguments