Reasonableness Revisited: Mason Re-affirms Law Of Judicial Review

• Law Firm: Torys LLP
• Subject Matter: Litigation, Mediation & Arbitration, Immigration, Trials & Appeals & Compensation, General Immigration
• Author: Ms Yael Bienenstock, Jon Silver, Alex Bogach and John Terry
• Published date: 03 October 2023

In 2019, the Supreme Court's landmark decision in Vavilov revamped the framework governing judicial reviews. Four years later, the Supreme Court has revisited that framework in Mason v. Canada (Citizenship and Immigration), 2023 SCC 21. In its decision, the Court re-affirmed the key principles from Vavilov that all reviewing courts must apply when assessing the "reasonableness" of an administrative decision.

What you need to know

Building on Vavilov, the Court in Mason provided the following guidance:

• No new correctness category. Reasonableness is the presumptive standard of review in applications for judicial review of administrative decisions. Mason does not alter this framework. The Court rejected an invitation to recognize a new category of cases in which correctness review applies (for certain types of immigration appeals). Writing alone on this point, Justice C'té would have recognized a new category.
• Reasonableness review starts with the decision under review. The Court doubled down on its framework from Vavilov for conducting reasonableness review. Reviewing courts must start with the reasons offered in the decision under review. Even when statutory interpretation is at issue, the reviewing court cannot conduct a preliminary analysis of the legislation before examining the administrative decision.
• Decisions with significant impacts require responsive justification. A reviewing court should conduct reasonableness review mindful of the impact of the decision on the affected individual. The Court took the opportunity to emphasize that where the impact of a decision on an individual's interests is severe, the decision-maker's justificatory burden is higher.
• The role of international law. The Court held that the administrative decision-maker's interpretation was unreasonable, in part, because it failed to address international law. Although international law is particularly important in the immigration context, the Court stressed the importance of the interpretive presumption that statutes conform with international law.

Judicial review of administrative action on the reasonableness standard

How courts review administrative decisions on the reasonableness standard

In most applications for judicial review of administrative action, judges must defer to "reasonable" decisions from administrative bodies. This includes the administrative body's legal conclusions, even when that judge may think that it is not the "best" or "correct" answer to the legal...