Reining in isn't even the concern; in Canada the oppressive methods extend FAR beyond simple "snooping". In my case; and presumably in the case of many others, we are experiencing draconian life pursuits and opportunity interference. I've had direct interference in two careers, though I have no criminal record or allegations...I even volunteered at a Home Hospice many years ago while in University. This interference occurred AFTER the corporations hired me (and I was experiencing success). It is an absolute Human Right violation both domestically and by International standards, truly shocking by any civilized standards, a dirty secret Canada wishes to keep hidden.
I have posted many examples of Canadian security apparatus abuses of Canadians Rights from the municipal police covert actions to Federal agency's database misuse (RCMP) and absurd and Gestapo-like obsession with information (and use of such flimsy information to ruin citizens right to pursue self-determination). You have the NSA, we have CSEC, that kind of innocuous spying doesn't concern me; direct persecution in citizens careers and personal lives, relationships and the like does.
When the Inspector General had the ability to view such abuses (my dossier for example), one had an outlet to ensure the actions were not as oppressive as they now can and will be and their ability to view, question and report back to the government would often provide enough of an incentive for CSIS to "self regulate". What government would suggest with a straight face that oversight of such a powerful agency is not in the populations interest?