Back to ‘Reasons First’: FCA Reinforces Vavilov in Canadian Nuclear Laboratories Ltd. v Canada (Attorney General)

At a Glance:

• The Federal Court of Appeal confirms that reasonableness review focuses on the adequacy of the decision-maker’s reasons, rather than reviewing courts substituting their own substantive analysis of the merits.
• Courts cannot reconstruct or supplement missing reasoning, even where the result might appear defensible.
• Post hoc explanations, including affidavits, generally cannot justify a decision because they do not speak to the reasonableness of the decision maker’s reasons and raise concerns about “bootstrapping.”
• Even where no formal reasons are required, the record must still permit a coherent and intelligible chain of analysis to support the decision.

The Federal Court of Appeal’s recent decision in Canadian Nuclear Laboratories Ltd. v Canada (Attorney General), 2026 FCA 106, reinforces the ‘reasons first’ approach to reasonableness review as articulated by the Supreme Court of Canada in Canada (Minister of Citizenship and Immigration) v Vavilov, 2019 SCC 65 (Vavilov).

The Federal Court of Appeal dismissed an appeal from a decision overturning the Minister of Environment and Climate Change Canada’s issuance of a permit under the Species at Risk Act, SC 2002, c 29.

While both the Federal Court and the Federal Court of Appeal found the Minister’s decision unreasonable, the Federal Court of Appeal reached that conclusion by focusing on the adequacy of the Minister’s reasons, and found that the Federal Court had wrongly focused on the substantive merits of the decision.

In this blog post, we consider the Federal Court and Federal Court of Appeal decisions, and their implications for how the Vavilov framework should be applied in cases without formal reasons.

Vavilov Precedent

In Vavilov, the Supreme Court of Canada clarified that the standard of review for administrative decisions is presumptively one of reasonableness, giving deference to the administrative decision-maker.

Reasonableness review requires a ‘reasons first’ approach, where the court considers the reasoning process followed by the decision-maker, including examining the written reasons. The court considers whether the decision-maker’s conclusion is supported by “an internally coherent and rational chain of analysis and that is justified in relation to the facts that constrain the decision-maker.” By focusing on the administrative decision-maker’s reasoning, the court gives deference to the decision-maker.

The Federal Court Decision (Kebaowek First Nation v Canada (Attorney General))

The Minister issued a permit to Canadian Nuclear Laboratories Ltd. under s. 73(3) of the SARA, allowing it to construct and operate a Near Surface Disposal Facility (NSDF) for low-level radioactive waste at its Chalk River Laboratories site.

The Federal Court found that the construction would result in habitat loss for protected species listed under Schedule 1 of the SARA. The decision to issue the permit was challenged by Kebaowek First Nation and several environmental organizations.

The Minister did not provide formal written reasons to support the decision to issue the permit. Instead, the Federal Court conducted judicial review based on a collection of documents from the decision-making record, including a science review conducted by Environment and Climate Change Canada.

The Federal Court overturned the Minister’s decision, finding that the Minister had applied a flawed interpretation of the requirements set out in s. 73 of the SARA, rendering the Minister’s decision unreasonable.

The Federal Court found that the Minister failed to address why consideration of “all reasonable alternatives” in site selection was limited to sites already owned by the AECL, and the Minister failed to provide justification for why the selected site was the “best solution” (a requirement under the SARA).

The Federal Court of Appeal Decision (Canadian Nuclear Laboratories Ltd. v Canada (Attorney General))

In Canadian Nuclear Laboratories Ltd v. Canada (Attorney General), the Federal Court of Appeal agreed that the Minister’s decision was unreasonable, but for different reasons. The key provision of the SARA, s. 73(3)(a), had never been previously interpreted.

The decision letter, permit and decision memorandum provided no insight into how the legislative provision was interpreted. Nor would the Federal Court of Appeal rely on an affidavit subsequently sworn by a civil servant because “affidavits submitted by administrative bodies raise concerns of ‘bootstrapping’ or making submissions to reviewing courts that are essentially new reasons supporting the administrative decision.”

As such, the decision did not reveal any statutory interpretation analysis in respect of the key provision of the SARA, s. 73(3)(a), and the Minister’s failure to justify its interpretation of s. 73(3)(a) made the decision unreasonable. The Court underscored the importance of “transparent and intelligible reasons” accompanying administrative decisions, as set out in Vavilov.

Section 73(3)(a) provides that the Minister must be of the opinion that “all reasonable alternatives to the activity that would reduce the impact on the species” have been considered. The Federal Court of Appeal criticized the Federal Court’s analysis of whether the Minister had considered “reasonable alternatives” as “out of step with” a “reasons first” approach, because it is for the Minister and not the Federal Court to interpret how “reasonable alternatives” must be determined.

Instead, the Federal Court of Appeal emphasized that the Minister must provide a rationale identifying which alternative sites were considered and what factors were considered in selecting those alternative sites. The Minister’s failure to do so made the decision unreasonable.

Similarly, s. 73(3)(a) requires the Minister to adopt “the best solution” available, and the Federal Court of Appeal emphasized that it was up to the Minister to interpret the meaning of “best solution” (not the Federal Court) but that the Minister’s reasoning must provide clarity as to that interpretation. Where the Federal Court had focused on the substantive problems with the Minister’s decision, the Federal Court of Appeal focused on the Minister’s failure to provide reasons justifying the decision.

The Court’s opinion is best summarized by its concluding paragraph:

While one could surmise why the East Mattawa Road site might have been a defensible choice as the “best solution” out of “all reasonable alternatives for the activity that would reduce the impact on the species”, it is not the court’s job to craft coherent reasons for administrative decisions. That is the Minister’s job, and the reasons here fall below the standard of justification required on reasonableness review.

What This Decision Clarifies

This decision is a clear example of applying the ‘reasons first’ framework from Vavilov. The adequacy of the decision-maker’s reasoning, rather than the merits of the decision, remains central to the reasonableness analysis. The Federal Court of Appeal’s critique of the Federal Court decision underscores that reviewing courts undertaking reasonableness review should not supplement or reconstruct the decision-maker’s reasoning, nor should they engage in their own merits-based analysis.

The decision is also clear that reasons provided after the fact through an affidavit, even if compelling, cannot be used to justify a decision due to concerns of “bootstrapping” by the decision-maker. The focus of reasonableness review is on the reasons actually given, not those that could have been given.

In Vavilov, the Supreme Court of Canada affirmed that there is not always an obligation to provide written reasons for all administrative decisions, and written reasons given by an administrative body should not be assessed against a standard of perfection.

In this case, no formal reasons were provided – nor were they required – but even when the court looked to the surrounding documents including a science review and decision memorandum, the permit and a public letter – no reasonable chain of reasoning could be discerned.

This case demonstrates that, even where no formal reasons are required, there must still be a sufficient record to allow for an analysis of the reasonableness of the administrative decision. If that is not present, the decision may not be reasonable, even if a substantive argument could be constructed for reasonableness, particularly where statutory interpretation is at issue.