A look at the constitutionality NAFTA:
[M]y proposition is that the United States-Canada dispute resolution provisions permit persons who are not officers of the United States, and who are not appointed under the Appointments Clause, to overrule federal officials who are officers of the United States
on the grounds that the officials did not follow United States law
. Not only does that scheme violate principles of representative government and democracy, but it also violates the Appointments Clause.
Alan Morrison, Public Citizen, Appointments Clause Problems in the Dispute Resolution Provisions of the United States-Canada FTA, 49 Wash. & Lee L. Rev. 1299-1300 (1992).
You may be interested in this.
Nice to see you've re-discovered the folks at Public Citizen.