I think because national security can be viewed broadly.... In fact, by including CBSA in the complaints mechanism, it would open up NSIRA to be able to dig into what's happening at the CBSA. In this case they will be able to go further.
However, at the same time, we need clarity on what constitutes national security so that on the other side it can't be shrunk in private to say that national security only means situations where somebody gets flagged on a no-fly list, or something like that, and that everything else, for example, refugees and similar issues, aren't considered.