When an individual is charged with a criminal offence in Canada, the state is required, as a general rule, to disclose all relevant information to the defence (see R. v. Stinchcombe,  S.C.J. No. 83, a landmark decision that forever altered the administration of justice in Canada).
For greater clarity, an accused is entitled to review all of the evidence that the state intends to tender at trial. The prosecution is not permitted to use the element of surprise. The Crown is prohibited from ambushing an accused with previously undisclosed information on the date of trial.
An accused is also entitled, as a general rule, to review all of the information that the police uncover during an investigation, even if the Crown does not intend to rely upon that information at trial (Stinchcombe at para. 19).
The Crown’s disclosure obligation is critical for preventing the conviction of the innocent. Any information that the police discover that is helpful to an accused must be revealed, not concealed. As stated by Sopinka, J. in Stinchcombe:
…the fruits of the investigation which are in the possession of counsel for the Crown are 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…(at para. 12).
Sopinka, J. went on to confirm that the “…failure to disclose impedes the ability of an accused to make full answer and defence” (at para. 17).
With respect to timing, an accused is entitled to receive disclosure after the police lay a charge and before making any decisions with respect to plea or whether a trial should take place before a judge or a jury (Stinchcombe at para. 28).
After a client is charged, defence counsel will make a formal request to the Crown Attorney for the disclosure materials.
Upon receipt, defence counsel must ensure that disclosure is complete. It is common for counsel to make requests for specific items of additional disclosure. In some cases, counsel may have to make seek judicial intervention if the Crown refuses a disclosure request.
Defence counsel must then review and analyze the disclosure materials. Counsel will also provide the client with an opportunity to personally review the disclosure. Counsel will take into account the client’s commentary when assessing the strengths and weaknesses of the case for prosecution.
A comprehensive review of the disclosure materials at an early stage allows defence counsel to provide practical advice as to the choices that are available to the client and a frank assessment of potential outcomes.
· There are exceptions to the state’s general obligation to disclose all relevant information. The Crown's legal duty is subject to a reviewable discretion with respect to restricting the release of information (for example, to prevent the disclosure of privileged information such as the identity of an informer) and controlling the timing of disclosure (for example, the Crown may delay disclosure so as not to undermine an ongoing investigation) (Stinchcombe at para. 20).