Is there any case law supporting the assertion of public interest privilege?

In Bourgeois v. Bolen (2004), 351 A.R. 246, 2004 ABQB 35, the plaintiff in a civil accident claim sought production of records showing the blood alcohol level of the defendant driver, which records were alleged to have been obtained in violation of the driver’s rights under the Canadian Charter of Rights and Freedoms. Greckol J. noted at para. 54 that the defendant in that case argued that “where documentation and information is produced under statutory compulsion to a servant of the Crown for a limited purpose, it should be held in strict confidence and used only for the limited purpose specified in the statute”. Greckol J. approved the reasoning in Niagara and added further comments at paras. 55, 66 and 68 with respect to the necessary balancing: The court in Niagara held that where information has been provided to a government department or agency under statutory compulsion, and is sought by parties to a civil action, public interest privilege against disclosure can be asserted and is to be dealt with by balancing the public interest in non-disclosure of confidential information gathered under compulsion against the public interest in making all relevant evidence available for the administration of justice. .... The notion of a public interest privilege or immunity exception to the inclusionary rule conforms ... with the fourth Wigmore condition, described by McLachlin C.J. in A.M. v. Ryan, 1997 CanLII 403 (SCC), [1997] 1 S.C.R. 157 at para. 29 as a requirement “that the interests served by protecting the communications from disclosure outweigh the interest of pursuing the truth and disposing correctly of the litigation.” .... The bar is high: for privilege to exist “... it must be shown that the benefit that inures from privilege, however great it may seem, in fact outweighs the interest in the correct disposal of the litigation” (per McLachlin C.J. in Ryan at para. 31).