Have journalists declare their political preferences?

So, we all know that reporting is biased, because there's no such thing as an objective viewpoint. In Canada we try to keep ourselves reasonably assured that the CBC, for example, reports political discussion fairly. In my opinion, it seems to work for us. But how can I know for sure? How can even they know they're being fair?

Rick bookstaber has a simple idea that makes you think: include political preferences of the reporter/editor in each story's byline.

The bad news is that this would fundamentally change the idea of journalism; on the other hand, maybe that's not such a bad idea at this point.

Update 2008/09/30: A convenient example of what I mean, via Peter Norvig. He admits his bias up front, then proceeds to produce as unbiased a report as he can manage. (And he does pretty well at it!) I wish such a thorough resource existed for the Canadian election.