Fettering of Discretion and the Reasonableness Test

In Canada, a global reasonableness test is supposed to be applied in the review of administrative decisions, even where the allegation is that the decision-maker abused its discretion. The Supreme Court said as much in 2003 (see paras. 22-25).

But some of the traditional grounds of review for abuse of discretion fit uneasily under the general rubric of reasonableness. Bad faith is one: surely a decision taken in bad faith is objectionable per se, with no need to ask whether the bad faith was unreasonable (if that question even makes any sense!).