The central issue before the Supreme Court was whether Cole had a reasonable expectation of privacy in the laptop. The Court found that he had. The warrantless search of it by the police was therefore a violation of section 8. The evidence, however, ought not to be excluded: 2012 SCC 53.
In considering this issue the majority, authored by Fish J, noted that the issue must be determined by a consideration of the “totality of the circumstances” [para 39]. This test is “one of substance, not form” [para 40]. The inquiry is guided by the following: (1) an examination of the subject matter of the alleged search; (2) a determination as to whether the claimant had a direct interest in the subject matter; (3) an inquiry into whether the claimant had a subjective expectation of privacy in the subject matter; and (4) an assessment as to whether this subjective expectation was objectively reasonable having regard to the totality of the circumstances [para 40].
In the present case, some of those circumstances included that the Policy and Procedure Manual of the school board asserted ownership over not only the hardware but also the data stored on it. However, it was recognized that Cole was permitted to use his laptop “for incidental personal purposes” as well.
Taking these considerations into account Fish J held:
While the ownership of property is a relevant consideration, it is not determinative (R. v. Buhay, 2003 SCC 30 (CanLII), 2003 SCC 30,  1 S.C.R. 631, at para. 22). Nor should it carry undue weight within the contextual analysis. As Dickson J. (later C.J.) noted in Hunterv. Southam, at p. 158, there is “nothing in the language of [s. 8] to restrict it to the protection of property or to associate it with the law of trespass”.
The context in which personal information is placed on an employer-owned computer is nonetheless significant. The policies, practices, and customs of the workplace are relevant to the extent that they concern the use of computers by employees. These “operational realities” may diminish the expectation of privacy that reasonable employees might otherwise have in their personal information (O’Connor v. Ortega, 480 U.S. 709 (1987), at p. 717, per O’Connor J.).
Even as modified by practice, however, written policies are not determinative of a person’s reasonable expectation of privacy. Whatever the policies state, one must consider the totality of the circumstances in order to determine whether privacy is a reasonable expectation in the particular situation (R. v. Gomboc, 2010 SCC 55 (CanLII), 2010 SCC 55,  3 S.C.R. 211, at para. 34, per Deschamps J.).
In this case, the operational realities of Mr. Cole’s workplace weigh both for and against the existence of a reasonable expectation of privacy. For, because written policy and actual practice permitted Mr. Cole to use his work-issued laptop for personal purposes. Against, because both policy and technological reality deprived him of exclusive control over — and access to — the personal information he chose to record on it [paras 51-54].
In the end Fish J held that Cole did have an objectively reasonable expectation of privacy in the laptop.
The remaining question of whether the conduct of the police infringed upon this privacy interest was then addressed.
First, Fish J rejected the notion that the fact “the school board had acquired lawful possession of the laptop for its own administrative purposes did not vest in the police a delegated or derivative power to appropriate and search the computer for the purposes of a criminal investigation” [para 67]’ [emphasis in original].
Second, Fish J rejected the notion that the police could have relied upon “third party consent”. In doing so Fish J appears to have rejected entirely the notion of third party consent in Canadian criminal law – the following comments are illustrative:
For consent to be valid, it must be both voluntary and informed. The adoption of a doctrine of third party consent in this country would imply that the police could interfere with an individual’s privacy interests on the basis of a consent that is not voluntarily given by the rights holder, and not necessarily based on sufficient information in his or her hands to make a meaningful choice [para 78].
This apparent blanket rejection of third party consent is curious. It is understandable, in the circumstances of this case, that third party consent could not be relied upon. However, it is much less clear that there is no such doctrine in Canadian criminal law. Indeed, it seems such a doctrine has been accepted in the past: see for example R v Desrochers, 2008 ONCA 255.
In the end, Fish J found that the warrantless search of the computer violated section 8 of the Charter.
The evidence, Fish J held, should not be excluded under section 24(2) [paras 80-98].