Members of the public who are uninitiated with the legal system in Canada are often confused when they encounter administrative law for the first time. The widely-recognized strengths of administrative tribunals, their flexibility and expediency, is often only possible because they discard some elements of formality and rigid procedure.
The relationship between reviewing courts and administrative tribunals is also constantly evolving. The Supreme Court of Canada in National Corn Growers Assn. v. Canada (Import Tribunal) resisted in 1990 an approach where courts would substitute the opinion over that of an administrative tribunal’s interpretation of a legislative provision, preferring greater curial deference. The rationale for this was that courts may not be well qualified to provide interpretation of an agency’s constitutive statute, as they may not fully understand the broad policy context that they work within.
But what happens when an administrative tribunal has multiple conflicting interpretations by different decision-makers? Tribunals do not strictly follow stare decisis, and other decisions are considered persuasive, and not binding. Paul Daly explains in The Principle of Stare Decisis in Canadian Administrative Law,
Canadian courts have long adopted a legal pluralistic view of the administrative process, allowing decision-makers to tailor their procedures to better meet their statutory objectives in regulatory environments that often change rapidly. Administrative decision-makers are, in short, “masters in their own house”. Accordingly, administrative decision-makers are permitted to take rules from the general law and modify them to the needs of a particular regulatory setting...
When acting within their jurisdiction, they may solve the conflict before them in the way judged to be most appropriate”. Simply put – and putting aside the misleading idea that stare decisis is a strait jacket worn beneath judicial robes – “an administrative tribunal is not bound by its previous decisions or the decisions of its predecessor”. As a result, administrative decision-makers have significant flexibility in responding to changes in regulatory context and may change policies to better suit changed circumstances. Previous decisions – especially a consistent line of previous decisions – “reveal where the lawhas been and where it may be headed” and may accordingly provide “a valuable benchmark against which to assess the [reasonableness of a] decision”.
The Court in Domtar Inc. v. Quebec (Commission d’appel en matière de lésions professionnelles) provided further justification for this approach in 1993,
If Canadian administrative law has been able to evolve to the point of recognizing that administrative tribunals have the authority to err within their area of expertise, I think that, by the same token, a lack of unanimity is the price to pay for the decision‑making freedom and independence given to the members of these tribunals. Recognizing the existence of a conflict in decisions as an independent basis for judicial review would, in my opinion, constitute a serious undermining of those principles. This appears to me to be especially true as the administrative tribunals, like the legislature, have the power to resolve such conflicts themselves. The solution required by conflicting decisions among administrative tribunals thus remains a policy choice which, in the final analysis, should not be made by the courts.
While the concurring reasons in Vavilov stated at para 286 that “Curial deference is the hallmark of reasonableness review,” the majority stated at para 24 that legislatures cannot shield administrative decision-making entirely from curial scrutiny, as judicial review is protect under s. 96 of the Constitution Act, 1867.
The majority also recognized at paras 71-72 the challenge of “persistent discord or internal disagreement within an administrative body leading to legal incoherence,” citing Domtar, but refused to create an additional category on this basis that would require correctness review on the basis of review of law. Instead, they indicated that a more robust reasonableness review would be sufficient, but there may be some circumstances in the future where such review could justify this type of judicial intervention,
 …we agree that the hypothetical scenario… in which the law’s meaning depends on the identity of the individual decision maker, thereby leading to legal incoherence — is antithetical to the rule of law… Moreover, the precise point at which internal discord on a point of law would be so serious, persistent and unresolvable that the resulting situation would amount to “legal incoherence” and require a court to step in is not obvious. Given these practical difficulties, this Court’s binding jurisprudence and the hypothetical nature of the problem, we decline to recognize such a category in this appeal.
The Ontario Divisional Court recently heard a judicial review in Tang v. Human Rights Tribunal of Ontario which reviewed these principles for the first time in this context in Ontario.
The application in this manner, complaining of discrimination on the grounds of disability, sex and sexual harassment, was deferred pending a workplace grievance. The request to re-activate it when the grievance was withdrawn was denied, as the grievance was withdrawn on a with prejudice basis by the arbitrator involved.
The Applicant also missed the tribunal’s deadline, but requested an order for it to be extended on the basis that her disability affected the timing of filing. The Tribunal reviewed the medical evidence provided, and found that it did not properly support the disability claim. The Applicant was also able to point to other tests used by the Tribunal in the extension of time, which were not used here.
The Divisional Court addressed this dichotomy as follows,
 The Tribunal acknowledged the existence of another line of decisions applying a different test for the granting of an extension of time for renewal of an application. However, it found that the test it was applying in this case was the test predominantly used in its jurisprudence…
 In this case the Tribunal cannot be said to have departed from a longstanding practice or established internal authority. It followed a line of cases followed on several occasions prior and on at least once occasion since. Although it may well be preferable that the Tribunal reach a measure of unanimity on the issue, its failure to do so does not render the decision unreasonable.
Given the enormous backlog of cases at the Human Rights Tribunal, cases are being dealt with differently than they have been in the past. This itself will inevitably create different lines of cases, but thus far does not appear to reach the level of persistent discord referred to in Vavilov.
The issue of conflicting jurisprudence post-Vavilov has been touched on at the Federal Court of Appeal, and the Court of Appeal for Northwest Territories, but none have risen to the level of legal incoherence that would be antithetical to the rule of law.