The phrase "impartial tribunal" means a fair and unbiased group that makes decisions without favoring any side or having any personal interest or prejudice. Full definition
[E] veryone is entitled to a fair and public hearing within a reasonable time by an independent and impartial tribunal established by law. (politics.stackexchange.com)
In an earlier phase of international investment, when investors were more likely to challenge outright expropriations or other forms of bad - faith conduct, the availability of impartial tribunals was seen as a valuable check on host state abuse. (prawfsblawg.blogs.com)
Plaintiff contends Justice J. FOLEY abandoned his role as the administrator of a fair and impartial tribunal in accepting case law introduced by the defendants counsel or injected on his own accord. (slaw.ca)