It's worth pointing out that one of the justices says it's not really that clear-cut. Justice Marie Deschamps wrote that providing a link to a false news website is definitely not defamatory in itself, but it could potentially be if the linker knew that it was false. In this particular case, however, the argument could not be made because it failed on one of the key tests to prove defamation -- that a receiving third party was made aware that the information was false, so she ruled for the defendants.
I did a quick check on the law on defamation in Canada, or at least the general principles around it. In the common law jurisdictions (the territories and all provinces except Québec) the courts have rejected the "actual malice" standard in the States (based on a 1964 SCOTUS ruling, New York Times v Sullivan, which ruled the 1798 Alien and Sedition Acts unconstitutional and essentially undercut the Confederate States' attempts to block protests against segregation merely by suing anyone, black or white, who challenged the morality of Jim Crow -- it was actually against the law in many of those states to sign a petition calling for the end to segregation, or to voluntarily desegregate a restaurant in an area where segregation was required). Actual malice requires "knowledge that the information is false" or was "published with reckless disregard of whether it was false or not."
Common law here instead states that fair comment, truth, responsible communication or privilege remain defences against defamation claims, whether the target is a public or private figure. Determining defamation goes on a case by case basis but it largely depends on who the target audience. (You may remember Benny Hinn's attempts against both the CBC and NBC back in 2005 to sue for damages based on his outlandish spending sprees, until he discovered the leaked documents proving where he stayed and dined were from his own ministry. In that case, broadcast media's target audience is everyone, the defence is freedom of the press.)
The standard in Québec is actually a mixture of common and civil law principles (in part because the colonial period where English standards of freedom of speech and religion became so imbued in the province's laws that it overtook some contradicting principles in older versions of the civil code). One of the most important of these is fair comment. Unlike the rest of Canada, there is not a strict liability standard, instead there is a standard of reasonableness. That is, someone who made a defamatory statement would not be liable if he or she honestly believed it was truthful.
The relevant Article of the province's Civil Code, 1457, reads:
Every person has a duty to abide by the rules of conduct which lie upon him, according to the circumstances, usage or law, so as not to cause injury to another.In the particular case here, I do not think there would have been a case under civil law anyway. We all put up hyperlinks in blog posts we write or e-mails we send. Unless we knew the information was definitely defamatory or patently false -- example, the Holocaust was exaggerated or a total lie -- why should we be held responsible? And even if we knew that, why should we be held responsible for a link even if it came with the advisory that we don't agree with the material but we're pointing it out so people know it's out there and being consumed by individual not as discerning as most are?
Where he is endowed with reason and fails in this duty, he is responsible for any injury he causes to another person by such fault and is liable to reparation for the injury, whether it be bodily, moral or material in nature.He is also liable, in certain cases, to reparation for injury caused to another by the act or fault of another person or by the act of things in his custody.
Once again, free speech wins. As it always should. There are strict limits as to what should not be allowed to be published or disseminated (e.g. child pornography) and it's good to know that a link, any link, does not fall within those bounds.