This error alone required the SCAJ to assess, without
deference to the trial judge, whether there was a basis on which
the warrant could have issued.
(3) The trial judge failed to consider whether the issuing
justice could have authorized the warrant
 I agree with the SCAJ that the trial judge’s analysis
reflects her own view as to whether the warrant should have been
issued. It was an error in law to fail to determine whether the
issuing justice could have authorized the warrant.
 The trial judge set out the governing principles correctly.
A warrant, once issued, is presumed to be valid. The role of the
reviewing judge is to determine whether there is at least some
evidence upon which the issuing justice could have issued the
warrant. The party challenging the warrant bears the burden
of demonstrating its invalidity. The reviewing judge is not to
engage in a fresh assessment of the grounds for the warrant or
substitute their views for those of the issuing justice. The task
of the reviewing judge is limited to assessing whether on the
whole of the record before the issuing justice, as amplified on
review, there is “at least some evidence that might reasonably
be believed on the basis of which the authorization could have
issued”: R. v. Araujo,  2 S.C.R. 992,  S.C.J. No. 65,
2000 SCC 65, at para. 51 (emphasis in original).
 Having stated these principles, the trial judge expressed
specific concerns she had with the ITO and concluded the
warrant should not have been issued. For the following reasons
I conclude, as did the SCAJ, that the trial judge’s concerns are
unsupported by the evidence and that the issuing justice, on the
totality of the evidence, could have authorized the warrant. In
fact, as I discuss below, the issuing justice could have taken a different view of each of the deficiencies found by the trial judge.
( i) The “disclaimer”
The trial judge’s reasons
 Cyber Tipline Reports contain two statements, preprinted
in the template used for its reports, which Cst. MacDonald did
not include in the ITO. As indicated above, the “disclaimer”
consists of a sentence plucked out of the paragraph in the header
of the first page, and the complete paragraph in the footer of
every page of the Cyber Tipline Report.
 The trial judge found that the failure to include the “
disclaimer” in the ITO would have misled the issuing justice. An
application for a search warrant is an ex parte proceeding and the