What is the scope of the defence's access to the affidavit supporting the application for an authorization to wiretap?

In dismissing the appeal, Charron J. wrote: 25 The first contextual factor that is ignored by the appellants’ argument has already been mentioned – the right to full disclosure. Under s. 187(1.4) of the Criminal Code, the defence has access to all the documents relating to the authorization. Access is granted on the simple assertion that the admissibility of the evidence is challenged and that access to the material is required in preparation for trial: Dersch v. Canada (Attorney General), 1990 CanLII 3820 (SCC), [1990] 2 S.C.R. 1505, at p. 1517. The material includes the affidavit filed in support of the application for an authorization. Subject to any necessary editing for the protection of informants, the affidavit will usually provide a comprehensive account of the investigation leading up to the wiretap application, an articulation of the grounds relied upon in support of the application, and information relevant to the reasonable believability of material gathered from informants. The affidavit filed in this case will be reviewed in detail later in these reasons. 26 In addition, under the principles established in Stinchcombe, the defence is entitled to all material in the possession or control of the Crown that is potentially relevant to the case, whether favourable to the accused or not. The defence can therefore compare the contents of the investigative file received from the Crown to the authorization’s supporting material to ascertain whether anything throws doubt on the reasonable believability of the latter. Further, the disclosure material may also provide the defence with possible third-party avenues of inquiry. 27 Hence, the defence does not arrive empty-handed at the evidentiary hearing. More importantly, if no basis can be shown for questioning the validity of the authorization on the strength of the disclosed material, it is generally unlikely that cross-examination of the affiant will provide further material information. I say it is unlikely because of the narrow focus of the inquiry on this evidentiary hearing…