Earlier this month a certain Liam McHugh-Russell uploaded a functional Canadian Legal Style to Zotero's style library here.
Look for the Canadian Guide to Uniform Legal Citation, 7th ed. (McGill Guide), Liam's style handles secondary sources perfectly, as far as I can tell, and performs well for cases and legislation.
When I asked him about the style, he did note that, due to the variety of formats in which citations to cases and legislation are offered online, the style cannot guarantee seamless downloading of citations to primary resources.
That said, I was able to extract a citation from CanLII, and with a bit of fiddling, produce this result in a footnote:
Canada (Public Safety and Emergency Preparedness) v Fabien, 2011 FC 472 (available on CanLII)
Which is pretty close to perfect. I had to remove a period after the v. supplied by CanLII, copy the complete neutral citation into the Reporter field, eliminate the content of the Date Decided field, and change the URL to "CanLII." Still, mutatis mutandis, I can now cite this decision accurately at the click of a button.
Thanks Liam. This is a very welcome contribution.