At the time of the legislation to outlaw smoking in pubs, I opposed a comprehensive ban on the grounds that the express aims of the legislation - to protect others from being harmed by the secondary smoke of smokers - could be achieved by ruling out smoking in pubs as a general rule, while permitting 'sealed areas... for smokers in some pubs, these areas to be serviced by no one other than those choosing to use them, except after the smoke has (been) cleared'. [See also here and here.] Well, in this country that battle was lost. But I'm interested to learn from what Alexi Duggins writes that 'in Canadian pubs... smokers have separate, well-ventilated rooms that staff do not enter'. If he's right about that, it's a mark in favour of Canada as compared with us.
The proposal now being mooted to ban smoking in cars is of a piece with the blanket ban on smoking in pubs. It's supposed to be about protecting children from the smoke of adults, a perfectly good objective. However, the appropriate - the justified - ban, given this objective, would be on smoking in cars carrying children. Duggins says:
The truth is that this debate isn't really about protecting children, just as the initial smoking ban wasn't really about protecting bar workers. It's about taking another step towards outlawing smoking altogether.
Maybe, maybe not. But it would be another law exceeding what purports to be its justification.