Originally Posted by Phrantic

It sounds like you're implying a couple things:
1.) Canadian Citizens don't commit crimes or shouldn't be examined upon returning to Canada.
2.) The right of privacy is paramout.

In fact, Canadian citizens have a lower expectation of privacy while crossing the border according to the Supreme Court of Canada. In my own personal opinion, the officer has a duty to determine whether or not a passenger in front of him deserves a second look through any questions posed.