What is the standard of review of a decision of the administrative tribunal?

To determine the standard of review, I must first decide whether the subject matter of the decision of the administrative tribunal was subject to a privative clause having full privative effect. If the conclusion is that a full privative clause applies, then the decision of the tribunal is only reviewable if it is patently unreasonable or the tribunal has made an error in the interpretation of a legislative provision limiting the tribunal’s powers. In either circumstance the tribunal will have exceeded its jurisdiction. These principles are summarized in U.E.S., Local 298 v. Bibeault, 1988 CanLII 30 (SCC), [1988] 2 S.C.R. 1048, at p. 1086: It is, I think, possible to summarize in two propositions the circumstances in which an administrative tribunal will exceed its jurisdiction because of error: 1. if the question of law at issue is within the tribunal’s jurisdiction, it will only exceed its jurisdiction if it errs in a patently unreasonable manner; a tribunal which is competent to answer a question may make errors in so doing without being subject to judicial review; 2. if however the question at issue concerns a legislative provision limiting the tribunal’s powers, a mere error will cause it to lose jurisdiction and subject the tribunal to judicial review. These two propositions derive their force in part from s. 96 of the Constitution Act, 1867. A legislature cannot completely insulate a tribunal from the superintending and reforming power of the superior courts. To attempt this would be to attempt to constitute the tribunal as a superior court: Crevier v. Attorney General of Quebec, 1981 CanLII 30 (SCC), [1981] 2 S.C.R. 220, 127 D.L.R. (3d) 1.