On that question, what I would say, not to oversimplify the process, is that the investigator—and I think this is what Sergeant Gilkes was getting at—has to do a lot of work in getting to his determination where he feels he's met reasonable grounds to suspect and is at the point where he can draft an affidavit and go before a judge.
On the face of it, it's a subjective decision to say that this is your suspect. What he'll be saying is, “I've interviewed people in the neighbourhood and I've done all my follow-up. I've done a whole bunch of investigational work to get to a point where I feel there's potential that this crime occurred, and I need more information. That's the suspect.” However, the investigator doesn't decide if that's the case. The judge decides whether the constellation of facts that have been presented in the affidavit meets what he or she feels are reasonable grounds to suspect and to grant the production order for a specific kind of information.
Just to clarify the subjectivity of it, any investigator in any police force, not just in Canada, has to get to a point where they've done enough work to determine that they suspect or believe that they have something to go to court with.