The Prerogative of Privacy: What Happens in Cabinet Stays in Cabinet

February 12, 2024 | Gerald D. Chipeur, KC, D. Josiah Allison


On February 2, 2024, the Supreme Court of Canada issued its unanimous decision in Ontario (Attorney General) v Ontario (Information and Privacy Commissioner), 2024 SCC 4 (“Ontario v. Ontario”), determining that “in our Westminster System of government, the executive-like the judicial and legislative branches … requires certain spheres of confidentiality to fulfill its constitutional role.” See Ontario v Ontario, at para 3. See also Re Canada Javelin Ltd., [1982] 2 SCR 686, at para 22 ([I]t seems to be well established that, at common law, the Crown enjoys a prerogative against being compelled to submit to discovery”).

In 2018, the newly elected government of Doug Ford was faced with a request from a CBC journalist to release the 23 mandate letters that Premier Ford had given to each of his Cabinet Ministers. Premier Ford refused, claiming that the mandate letters were exempt under section 12(1) of Ontario’s Freedom of Information and Protection of Privacy Act (“Act”).

The journalist appealed to the Information and Privacy Commissioner (“Commissioner”). The Commissioner found that the mandate letters were not exempt under the Act and ordered disclosure to the journalist. Premier Ford sought judicial review in the Ontario Divisional Court. That Court upheld the decision of the Commissioner, and a majority of the Court of Appeal agreed with Justice Lauwers of the Court of Appeal in dissent.

The Supreme Court of Canada did not agree with the Commissioner. Cabinet confidentiality with respect to the mandate letters was upheld for three reasons:

  1. The “separation of powers” protects the spheres of confidentiality necessary for the executive branch “to perform its constitutionally–assigned functions” (British Columbia (Attorney General) v Provincial Court Judges Association, 2020 SCC 20, at para 66);
  2. Confidentiality grants the executive the latitude necessary to govern in an effective, collectively responsible manner (Babcock Canada (Attorney General), 2002 SCC 57, at para 15);
  3. Confidentiality is “essential to good government”, as it promotes deliberative candour, ministerial solidarity, and governmental efficiency (Carey Ontario, [1986] 2 SCR 637, at 658-59);

See Ontario v. Ontario, at para 3.

Both the Constitution and section 12(1) of the Act required privacy for the “substance of deliberations” of Cabinet. The mistake of the Commissioner was to consider the mandate letters to be the outcomes of the executive decision making process, when in fact the mandate letters were properly characterized as the commencement of that process.

The Supreme Court of Canada agreed with the dissent of Justice Lauwers of the Court of Appeal that the fundamental reason for deliberative secrecy in Cabinet is effective government. This requires the Commissioner to interpret section 12(1) of the Act in a manner broad enough to protect communication necessary for the executive to function effectively. See Ontario (Attorney General) v. Ontario (Information and Privacy Commissioner), 2022 ONCA 74, at paras 187 and 208.


Efficient government was also the focus of the House of Lords in Conway v. Rimmer, [1968] AC 910 (HL) at 952, where Lord Reid wrote:

[The premature disclosure of Cabinet secrets] would create or fan ill-informed or captious public or political criticism. The business of government is difficult enough as it is, and no government could contemplate with equanimity the inner workings of the government machine being exposed to the gaze of those ready to criticise without adequate knowledge of the background and perhaps with some axe to grind.

According to the Supreme Court of Canada, it is the prerogative of the Premier (the executive branch) to determine when and how to announce Cabinets decisions is grounded in the harmful impact that premature disclosure of policy priorities can have on the deliberative process. The Court relied on the explanation of Professor Campagnolo for the convention that the deliberative process justifies “keeping Cabinet proceedings confidential until a final decision is made and announced by Ministers” (Behind Closed Doors: The Law and Politics of Cabinet Secrecy (2021) at 26).


It is important to note that six of the seven Supreme Courts of Canada set aside the Commissioner’s decision based upon the very low standard of review for “reasonableness”. See Ontario v. Ontario, at para 57.

Justice Côté was not prepared to review the Commissioner’s decision on the basis of reasonableness:

For the reasons I explain below, I would consider the issue raised in this appeal – the scope of Cabinet privilege – to be a general question of law of central importance to the legal system as a whole. I would therefore review the Information and Privacy Commissioner’s decision on a standard of correctness.

See Ontario v. Ontario, at para 65.

Justice Côté was correct.


The decision of the Supreme Court of Canada in Ontario v Ontario involved the prerogative of a provincial Cabinet to maintain secrecy over its communications and decision making process.

It is important to keep in mind the statutory privilege granted to the Federal Cabinet under section 39 of the Canada Evidence Act. That section reads:

Where a minister of the Crown or the Clerk of the Privy Council objects to the disclosure information before a court, person or body with jurisdiction to compel the production of information by certifying in writing that the information constitutes a confidence of the Queen’s Privy Council for Canada, disclosure of the information shall be refused without examination or hearing of the information by the court, person or body.

In the recent Federal Court decision in Parker v Canada (Attorney General), 2021 FC 496 (“Parker”), the Attorney General of Canada asserted Cabinet privilege against the production of certain evidence, but did not file a “Section 39 certificate” with the Court. This led the Federal Court to conclude that section 39 of the Canada Evidence Act did not apply, but that the common law relating to Cabinet confidentiality remained in place. Associate Chief Justice Gagne proceeded to require the Attorney General to disclose the materials to the Court and indicated that “the Court will conduct its own analysis to determine whether the materials … properly come within the definition of Cabinet confidentiality, and if so, whether the public interest in disclosure outweighs its secrecy”. See Parker, at para 39.

The decision in Ontario v Ontario may impact the approach of the Federal Court to assertions of common law Cabinet confidentiality. It appears that there is no longer room for a weighing of the public interest. Once Cabinet confidentiality has been properly asserted, that is the end of the analysis. When the Supreme Court of Canada required the Commissioner to give meaningful weight to the “traditions and constitutional conventions concerning Cabinet confidentiality,” no balancing with the public interest in disclosure was referenced. See Ontario v Ontario, at para 58.


In conclusion, it is necessary to reference the decision of Justice Mosley in Canadian Constitution Foundation v Canada (Attorney General), 2022 FC 1233 (“CCF”). In that case, Justice Mosley was asked to disregard section 39 certificates and order the disclosure of Cabinet confidences. Justice Mosley refused the request, because it was not necessary to his judicial review of the decision to invoke the Emergencies Act. However, he did conclude that there could be circumstances where a Court might look behind a claim of Cabinet confidentiality under section 39. See CCF, at para 115 (“the determinative question is whether the s. 39 Certificate immunizes the impugned decision from judicial review in a manner inconsistent with the rule of law”).

In CCF, Justice Mosley found that the Attorney General of Canada took adequate steps to avoid that conclusion. See CCF, at para 120 (“The Respondent’s voluntary disclosure of the redacted minutes and agendas in July undermines the argument that it has attempted to immunize the impugned decision from judicial review in a manner inconsistent with the rule of law.”).

This article was originally published by Law360 Canada, part of LexisNexis Canada Inc.


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