I would imagine some examples would be:

- personal drug use (of any kind) - bans on same-sex marriage (which I just looked up, and seems to be legal in Canada anyway) - any form of gun control

I'm not saying that I do or do not think the above should be legal, but they all are examples of "we know what's best for you". I think that's what the GP commenter was alluding to.

all of these have been ruled unconstitutional by the Canadian supreme court at one point or another.