Justice Karakatsanis wrote as follows (at paras. 1-3, 62-65, 67-68):

"In sexual offence cases, the Criminal Code, R.S.C. 1985, c. C-46 , limits the disclosure of private records relating to complainants and witnesses. The relevant provisions, ss. 278.1 to 278.91 , known as theMills regime, permit disclosure only where a record is likely relevant and its disclosure is necessary in the interests of justice. The regime applies to “records” that contain personal information for which there is a reasonable expectation of privacy, unless they are made by persons responsible for the investigation or prosecution of the offence. The issue on appeal is whether these provisions apply to police occurrence reports prepared in the investigation of previous incidents involving a complainant or witness and not the offence being prosecuted. The question is whether these unrelated police occurrence reports count as “records” as defined in s. 278.1 , such that the statutory disclosure limits apply.

I conclude that the Mills regime applies to police occurrence reports that are not directly related to the charges against the accused. Privacy is not an all or nothing right. Individuals involved in a criminal investigation do not forfeit their privacy interest for all future purposes; they reasonably expect that personal information in police reports will not be disclosed in unrelated matters. Moreover, while the regime exempts investigatory and prosecutorial records, that exemption applies only to records made in relation to the particular offence in question.

Accordingly, I agree with the trial judge that the unrelated police occurrence reports at issue were “records” within the definition of s. 278.1 and thus subject to the Mills regime. The trial judge was entitled to conclude that the reports should not be disclosed.

…

The respondent and the intervener the Criminal Lawyers’ Association of Ontario raise concerns about the effect of an expansive interpretation of “records” in s. 278.1 on trial fairness. A broad interpretation of “records” means that the Mills regime applies to a larger number of documents. While this furthers Parliament’s objective of protecting the privacy of complainants and witnesses, it may also impose procedural burdens on defendants and create the risk that some helpful documents would not be available to the defence. However, largely for the reasons set out in Mills, I do not think these concerns require a narrower reading of s. 278.1 .

Documents protected by the Mills regime are not inaccessible to the defence. Defendants can access records when the privacy infringement is proportionate, given the relevance of the record to the defence. Where the Crown plans to use information from police occurrence reports as part of its case against an accused, disclosure of that information will always be in the interests of justice. In Mills, this Court held that the process for accessing documents was adequate to preserve the constitutionality of the regime.

The principles of fundamental justice and trial fairness do not guarantee defence counsel the right to precisely the same privileges and procedures as the Crown and the police (Mills, at para. 111). Nor is the right to a full answer and defence a right to pursue every conceivable tactic to be used in defending oneself against criminal prosecution. The right to a full answer and defence is not without limit.

Because the Crown is an officer of the court, with undivided loyalty to the administration of justice, the Crown is not in an adversarial role in relation to its disclosure obligations. The information obtained through investigation is “not the property of the Crown for use in securing a conviction, but the property of the public to be used to ensure that justice is done” (Stinchcombe, at p. 333). The Crown has an obligation under s. 278.2(3) of the Criminal Code , to notify the accused of records in its possession covered by the Mills regime. Moreover, as discussed above, both police and Crown have common law duties aimed at ensuring proper disclosure, which apply notwithstanding the application of the Mills regime.

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It follows … that the police occurrence reports mentioned in the CBC radio documentary were subject to the Mills regime for disclosure, not Stinchcombe. The trial judge was right to require a Mills application before disclosing them to the defence, and the Court of Appeal was wrong to interfere. The trial judge’s application of the Mills regime was not challenged before us.

I would grant the motion to strike para. 10 of the respondent’s factum, but dismiss the motion to strike para. 11. I would also grant the motion to strike the appellant’s reply factum."

Note: This summary is drawn from Eugene Meehan’s SupremeAdvocacy Weekly Updates for the Law Community.