Everything on that website is directly applicable to Canada. The only issues that might arise are the ones that Zulutango brought up. Other then that, so long as your are in a "public place" you can take pictures of whatever or whoever you want.
The law is pretty clear on the issues of photography in common law countries. These issues was addressed many times in cases where celebrities tried to bar paparazzi's from taking their pictures in public.
Some cases that come to mind are John v Associated Newspapers Ltd.
, where Sir Elton John was photographed walking out of his car, wearing a track suit, so he sued the newspaper and wanted the House of Lords to grant an injunction from publishing those pictures in the newspaper. He lost the case, because he was in a "public place" and thereby, anyone can take a picture of him.
Another case that was quite controversial was Campbell v Mirror Group Newspapers
. Basically what happened there, Naomi Campbell was photographed leaving a rehab clinic. The picture was taken when she left the front door of the clinic and walked down a few steps directly into a parked limo. The picture was taken in that little interval when she was walking down the stair of a "public place". House of Lords held controversially that this did not constitute a public place, but was an extension of a private place (rehab clinic) and she could have relied on her reasonable expectation of privacy.
Although the cases above do represent issues of photography in relation to ordinary citizens so to speak and not figures of authority (like police), the police are not granted any immunity simply because they are police. Once again, the only limitations that come into my head are the same ones brought up by Zulutango.
Also, photography is a form of expression/freedom of press that is protected under Canadian Charter of Rights and Freedoms, s. 2(b). These rights can be enforced "vertically" or against the government and its agents, or entities carrying a governmental function (provincially funded hospitals for instance).
Here is something that might be of interest to you. This is the law as it is in Ontario, so there might be a few minor differences from province to province but I would say this pdf is directly applicable to the law here in BC: http://media.ambientlight.ca/wp-cont...-Laws-V1.0.pdf