If you mean judicial review on administrative law grounds, it is necessary to show that the applicant for judicial review has a particular interest in the administrative decision (e.g. - has been denied a licence of some sort).
If you mean judicial review on constitutional grounds, it is also necessary to show some sort of personal interest, although the law on standing for constitutional matters is a bit more open than the test for standing in administrative matters. The Supreme Court has held that in rare circumstances, a private citizen can sue on constitutional grounds, even without a clear personal interest, because ultimately all citizens have an interest in the due enforcement of the law. But the Court’s test for such standing is quite rigourous.
There is no need to ask the Crown’s permission to file a constitutional challenge. Anyone with fifty bucks and a computer can turn out a Statement of Claim and file it with the Court. Depending on the nature of the claim, the plaintiff would likely have to give notice of constitutional question to the federal and provincial Crowns, but neither one needs to give permission. They could argue in court that the plaintiff doesn’t have standing, but that decision lies with the Court, not the Crown.
In fact, the Supreme Court has held that a law that attempts to bar constitutional review of a statute is itself unconstitutional: Amax Potash v. Government of Saskatchewan.
