The facts are straightforward. M entered into a settlement agreement with the Ontario Securities Commission in 2008, in respect of misconduct that occurred in 2001. As part of the agreement M was barred from various activities in Ontario.
In 2010, the British Columbia Securities Commission made an order against M under a statutory provision that allows it to impose sanctions on a person who "has agreed with a securities regulatory authority, a self regulatory body or an exchange, in Canada or elsewhere, to be subject to sanctions, conditions, restrictions or requirements". These 'secondary proceedings' were based on the settlement agreement concluded in Ontario.
The difficulty raised by M was that the Commission's home statute contains a limitation period provision to the effect that the Commission cannot commence proceedings "more than 6 years after the date of the events that give rise to the proceedings". Were the "events" the underlying misconduct, which ended in 2001, as M contended, thus barring the secondary proceedings? Or were the "events" the settlement agreement entered into in 2008? Ultimately, the Court accepted the Commission's interpretation.
In its very brief order, the Commission did not explain its interpretation of the limitation period provision. It simply made an order barring M from activities in British Columbia for the same periods she was barred from activities in Ontario. (In passing, Canada does not have a national securities regulator, hence the need for the individual provincial regulators to conduct parallel proceedings of this nature.)
The fact that the Commission did not explain its interpretation of the term "events" did not particularly trouble the Court:
I find this somewhat troubling. Canadian courts have been taking a somewhat laissez-faire attitude towards after-the-fact rationalizations of administrative decisions. In the United States, by contrast, deference is not paid to administrative decision-makers' interpretations of law advanced for the first time in litigation. The individual subject to the authority of the administrative decision-maker should have the opportunity to argue his or her case on the record in full knowledge of the decision-maker's position on the relevant interpretive questions. This also makes other interested parties aware of the decision-maker's position. Allowing a decision-maker to put a thumb on the scales after the event is unfair and prevents a full airing of all relevant issues. Unlike Alberta Teachers, in the case at bar, we do not have the benefit of the Commission’s reasoning from its decisions in other cases involving the same issue (see paras. 56-57). However, a basis for the Commission’s interpretation is apparent from the arguments advanced by the respondent, who is also empowered to make orders under (and thus to interpret) ss. 161(1) and (6). These arguments follow from established principles of statutory interpretation. Accordingly, though reasons would have been preferable, there is nothing to be gained here from requiring the Commission to explain on remand what is readily apparent now.
The Court concluded that it should defer to the Commission's interpretation. In doing so, it reaffirmed the "categorical" approach it set out in Dunsmuir. There are some categories of question to which reasonableness applies (in particular, interpretations of home statutes, see paras. 19-22); some to which correctness applies. As I have observed elsewhere, however, the appeal of these categories is superficial; as in previous decisions, the Court had to do quite a bit of work to find the appropriate category.
Here, M argued cogently that the question of the proper interpretation of the limitation period provision was one of general law of central importance to the legal system. Such provisions appear in securities statutes across the country. And the underlying principles of limitation of actions are common to public and private law regimes.
Yet the Court -- as it has consistently done since Dunsmuir -- applied a standard of reasonableness:
 Here, the appellant’s arguments in support of her contention that this case falls into the general question category fail for three reasons. First, although I agree that limitation periods, as a conceptual matter, are generally of central importance to the fair administration of justice, it does not follow that the Commission’s interpretation of this limitation period must be reviewed for its correctness. The meaning of “the events” in s. 159 is a nuts-and-bolts question of statutory interpretation confined to a particular context. Indeed, the arguably complex legal doctrines such as discoverability that the appellant says demand correctness review (see A.R.F., at para. 9) have been specifically excluded from any application to s. 159...Accordingly, there is no question of law of central importance to the legal system as a whole, let alone one that falls outside the Commission’s specialized area of expertise.
 Second, while it is true that reasonableness review in this context necessarily entails the possibility that other provincial and territorial securities commissions may arrive at different interpretations of their own statutory limitation periods, I cannot agree that such a result provides a basis for correctness review — and thus judicially mandated “consisten[cy] . . . across the country” (A.R.F., at para. 13). No one disputes that each of the provincial and territorial legislatures can enact entirely different limitation periods... If there is a problem with such a hypothetical outcome, it is a function of our Constitution’s federalist structure — not the administrative law standards of review.
 Third, and most significantly, the problem with the appellant’s argument is her narrow view of the Commission’s expertise. In particular, the appellant argues that limitation periods “are not in themselves part of substantive securities regulation, the area of the [Commission’s] specialised expertise” (A.R.F., at para. 9). The argument presupposes a neat division between what one might call a “lawyer’s question” and a “bureaucrat’s question”. The logic seems to be that because the meaning of “the events” in s. 159 cannot possibly require any great technical expertise — there is, after all, no specialized “bureaucratese” to interpret — why should the matter be left to the Commission?
 While such a view may have carried some weight in the past, that is no longer the case. The modern approach to judicial review recognizes that courts “may not be as well qualified as a given agency to provide interpretations of that agency’s constitutive statute that make sense given the broad policy context within which that agency must work”...At this point, I am tempted to ask: why not just double down on Dunsmuir and apply a standard of reasonableness all the time? Retaining categories that the Court refuses to use only creates confusion. It is hardly an appropriate use of the Court's resources to keep slaying correctness dragons which emerge from provincial Courts of Appeal: Nor-man (Manitoba); Irving Paper (New Brunswick); and now McLean (British Columbia) all involved perfectly plausible examples of questions of general law of central importance to the legal system. A series of other cases involved perfectly plausible examples of jurisdictional questions (notably, Moldaver J approvingly referenced (at para. 25) the recent SCOTUS decision to largely do away with jurisdictional error). Maybe it is time to do away with these categories altogether and impose reasonableness review across the board?
There is also some interesting discussion of the meaning of reasonableness. The Federal Court of Appeal, New Brunswick Court of Appeal and Ontario Court of Appeal have each independently suggested that where the application of the traditional tools of statutory construction gives a "clear" answer to a question of statutory interpretation, courts are duty bound to insist upon it. Deference will only be given if the term in question is ambiguous. In today's decision, Moldaver J. took a similar approach:
 In plain terms, because legislatures do not always speak clearly and because the tools of statutory interpretation do not always guarantee a single clear answer, legislative provisions will on occasion be susceptible to multiple reasonable interpretations...Indeed, that is the case here, as I will explain in a moment. The question that arises, then, is who gets to decide among these competing reasonable interpretations?
 The answer, as this Court has repeatedly indicated since Dunsmuir, is that the resolution of unclear language in an administrative decision maker’s home statute is usually best left to the decision maker. That is so because the choice between multiple reasonable interpretations will often involve policy considerations that we presume the legislature desired the administrative decision maker — not the courts — to make. Indeed, the exercise of that interpretative discretion is part of an administrative decision maker’s “expertise”....
It is puzzling that Moldaver J did not mention the growing appellate jurisprudence on this question, but today's majority reasons are cut from the same cloth. It will not always be the case that a particular provision permits multiple reasonable interpretations. Where the ordinary tools of statutory interpretation lead to a single reasonable interpretation and the administrative decision maker adopts a different interpretation, its interpretation will necessarily be unreasonable — no degree of deference can justify its acceptance; see, e.g., Dunsmuir, at para. 75; Mowat, at para. 34. In those cases, the “range of reasonable outcomes”...will necessarily be limited to a single reasonable interpretation — and the administrative decision maker must adopt it. (Emphasis original)
Moldaver J then went on to assess the reasonableness of the Commission's interpretation. Having regard to the ordinary meaning, legislative history and context of the limitation period provision, he took the view that both M's preferred interpretation and the Commission's interpretation were reasonable. With the Commission's thumb on the scales because of the deference afforded its after-the-fact explanation of its position, the Court had no choice but to uphold the Commission's interpretation:
 The bottom line here, then, is that the Commission holds the interpretative upper hand: under reasonableness review, we defer to any reasonable interpretation adopted by an administrative decision maker, even if other reasonable interpretations may exist. Because the legislature charged the administrative decision maker rather than the courts with “administer[ing] and apply[ing]” its home statute (Pezim, at p. 596), it is the decision maker, first and foremost, that has the discretion to resolve a statutory uncertainty by adopting any interpretation that the statutory language can reasonably bear. Judicial deference in such instances is itself a principle of modern statutory interpretation.
 Accordingly, the appellant’s burden here is not only to show that her competing interpretation is reasonable, but also that the Commission’s interpretation is unreasonable. And that she has not done. Here, the Commission, with the benefit of its expertise, chose the interpretation it did. And because that interpretation has not been shown to be an unreasonable one, there is no basis for us to interfere on judicial review — even in the face of a competing reasonable interpretation...
Finally, Moldaver J. acknowledged that the Commission's interpretation could lead to harsh results in individual cases, but that in such cases, the Commission's decisions could well be unreasonable (see paras. 61-66). In the end, the Commission’s interpretation is a reasonable one because it furthers the legislature’s manifest goal of improving interprovincial cooperation. The appellant’s interpretation, by contrast, fits uneasily with the broader indicators of legislative intent available to us. In reducing s. 161(6) to a belts-and-suspenders codification of what is already common practice, her interpretation does little to improve interprovincial cooperation. I do not say that the appellant’s interpretation is inconsistent with such efforts — only that it does not further them to the same extent as the Commission’s interpretation.
Of course, the practical effect of the across-the-board reasonableness review I am suggesting may be modest: I suspect that reasonableness review on questions of law will end up being more intrusive; this goes back to my scepticism about the categorical approach. And my views on reasonable interpretations of law are not those of Canada's Courts of Appeal. I will have more on this in a future post.