Beyond Sault Dock: Court of Appeal for Ontario Reframes Test for Leave to Appeal in Knauff v. Ontario (Human Rights Tribunal)

For the first time in more than 50 years, the Court of Appeal for Ontario has updated its test for leave to appeal from a decision of the Divisional Court. In Knauff v. Ontario (Human Rights Tribunal) (“Knauff”),^[1] a five-judge panel confirmed that the test for leave is whether the proposed appeal raises an arguable question of law or mixed law and fact that is of sufficient public importance to warrant consideration by the Court of Appeal.

While these factors have always been considered, the new approach appears to move away from what many have seen as a categorical approach and toward a more flexible framework.

Key Takeaways

• The governing question is whether the proposed appeal raises an arguable question of law or mixed law and fact that is of sufficient public importance to warrant consideration by the court.
• Public importance is not confined to closed categories. It can arise from the breadth and significance of the interests affected by the immediate decision, but it can also come from the question’s importance to the development of the law of Ontario as a whole.
• The same framework applies regardless of whether the Divisional Court exercised its original jurisdiction (e.g., on judicial review) or its appellate jurisdiction, including on interlocutory decisions.
  

Background

A decision of the Divisional Court can only be appealed to the Court of Appeal with leave (i.e., permission) from the Court of Appeal and on a question of law or mixed fact and law.

Since 1972, the leading authority has been Re Sault Dock Co. Ltd. and the City of Sault Ste. Marie (“Sault Dock”).^[2] In that case, the court identified several examples of cases that might warrant leave, including disputes involving the interpretation of statutes, constitutional questions and significant questions of legal principle.

Over time, however, parties increasingly treated those examples as a rigid checklist. In West Whitby Landowners Group Inc. v. Elexicon Energy Inc.,^[3] the court expressed concern that this approach failed to reflect both the flexibility intended by Sault Dock and developments in constitutional, administrative and public law. Shortly afterward, Davis v. Aviva General Insurance Company^[4] confirmed that Sault Dock continued to govern unless reconsidered by a five-judge panel.

Against this backdrop, the court convened a five-judge panel to decide whether Sault Dock should continue to govern and, if so, in what form.

The New Test for Leave to Appeal

In a unanimous decision written by Justice Zarnett, the Court of Appeal held that the “essential message” of Sault Dock continues to govern but updated and clarified its application. The updated framework has two distinct but overlapping components: arguability and public importance.

This test applies regardless of whether the Divisional Court’s decision was an appeal or a judicial review (e.g., original jurisdiction).

Arguability

The first component asks whether the proposed appeal raises a real and debatable question between the parties arising in the circumstances of the case. The moving party does not need to demonstrate that the appeal will succeed or result in a different outcome than the one reached by the Divisional Court but must identify a genuine appellate issue arising from the circumstances of the case. If the issue is really only about the facts, an appeal will not be arguable as no appeal lies on a question of fact alone.

Public Importance

If the arguability component is met, the court then considers whether the arguable question of law or mixed law and fact is of public importance. The court emphasized that there is no closed category of questions capable of meeting this requirement. Instead, public importance is assessed from two perspectives:

• First, who will be affected by the resolution of the issue and the significance of those effects. The more persons who may be affected, and the more fundamental the interests at stake, the more likely the issue is to be one of public importance.
• Second, how the law of Ontario will be affected by resolving the question. This inquiry focuses on whether the issue bears on the development, progress, coherence, predictability and stability of Ontario law.
  

Concepts like special circumstances, miscarriage of justice and clear errors each no longer operate as separate categories but are broader considerations as to whether the question is one of public importance. Constitutional questions, novel issues, conflicting jurisprudence and areas lacking authoritative guidance may all indicate that an issue is of public importance.

Analysis

The Court of Appeal in Knauff framed its approach as a refinement, rather than a rejection of Sault Dock. Nevertheless, the case should change how parties approach leave applications moving forward.

The most important clarification may be the rejection of a categorical approach. Litigants do not need to demonstrate that their case fits within one of the Sault Dock examples or invoke an ill-defined residual category. This approach provides greater flexibility to address modern issues that do not fit neatly within the 1972 framework and clarifies when private law decisions should get leave to appeal.

Likewise, the court’s affirmation that the test does not differ depending on the nature of the appeal – whether the Divisional Court exercised original or appellate jurisdiction – provides welcome clarity.

Of course, the question on everyone’s mind is whether Knauff will make it easier or more difficult to obtain leave to appeal from a Divisional Court decision. The answer appears to be: it depends. Certainly, cases – including private law decisions – that deal with important legal questions but do not fit into the Sault Dock categories appear to have a better (or at least clearer) argument than they did previously. However, a “clear error” on its own no longer represents a straight path to getting leave. Instead, a moving party will have to argue that the error of the Divisional Court is so significant that it could affect the development of the law unless the Court of Appeal corrects it. This could be a substantial hurdle.

The Court of Appeal does not normally release reasons on leave motions, which will make it difficult to know how Knauff is treated in practice. However, as more final decisions are released in appeals where leave was granted, we should begin to see just how much of a change Knauff actually represents.

The Litigation & Dispute Resolution Group at Aird & Berlis LLP provides full-service representation across all forms of dispute resolution, including civil litigation, regulatory and administrative proceedings, appeals, mediation, arbitration and other alternative dispute resolution processes. Please contact the authors or a member of the group if you have any questions or require assistance.

[1] 2026 ONCA 653.