Canadian defamation law is easier to trigger than most people think and harder to defend than most people hope. The good news is that a few habits can reduce the risk.
What a plaintiff has to prove
The Supreme Court of Canada set out the test in Grant v. Torstar, 2009 SCC 61. A plaintiff must show three things:
- The words were defamatory. They would tend to lower the person's reputation in the eyes of a reasonable person.
- The words referred to the plaintiff. Leaving out a name does not help if readers can tell who you mean.
- The words were published. Communicated to at least one person other than the plaintiff.
That is a low bar. Notice what is missing: the plaintiff does not have to prove the statement was false or that you meant harm. Once those three elements are shown, falsity and damage are presumed. The burden shifts to you to prove a defence.
What "published" means online
Publication is broad. A post, a comment, a review, a group chat message and an email forwarded to one colleague all count. So does a repost: every person who repeats a defamatory statement publishes it again.
Two limits matter. A bare hyperlink, without more, is not publication of the linked content (Crookes v. Newton, 2011 SCC 47). That does not shield accompanying words that repeat the allegation or themselves convey defamatory meaning. And a private message to only the person you are criticizing is not publication, though it may raise other issues.
The main defences
| Defence | What you must show | Where people go wrong |
|---|---|---|
Truth (justification) | The sting of the statement is substantially true | Believing it is not enough; you need evidence you could put before a court |
Fair comment | Opinion on a matter of public interest, based on facts stated or known, that someone could honestly hold (WIC Radio v. Simpson, 2008 SCC 40) | Dressing a factual accusation as opinion: "I think he steals from clients" is still an allegation of fact |
Responsible communication | A matter of public interest, with diligent efforts to verify the allegations in the circumstances, including whether the other side was sought and accurately reported (Grant v. Torstar) | Available to non-journalists too; a one-sided post may fail the diligence test |
Qualified privilege | A duty or interest to communicate to someone with a matching interest, such as a reference or a complaint to a regulator | Lost if you send it to a wider audience than needed, or act from malice |
Anti-SLAPP protection in Ontario
Ontario’s Courts of Justice Act, s. 137.1, lets a defendant ask the court to dismiss a defamation claim early when it arises from expression on a matter of public interest. The Supreme Court explained the test in 1704604 Ontario Ltd. v. Pointes Protection, 2020 SCC 22. Once the defendant establishes that threshold, the plaintiff must show grounds to believe the claim has substantial merit and the defendant has no valid defence. The plaintiff must also show that the harm is sufficiently serious that the public interest in allowing the claim to proceed outweighs the public interest in protecting the expression.
This can protect public criticism, but it is not automatic immunity. Personal attacks and deliberate falsehoods can weigh against protection, but they do not automatically defeat an anti-SLAPP motion. In Bent v. Platnick, 2020 SCC 23, the majority allowed a claim to proceed because the plaintiff met both the merits-and-defences threshold and the public-interest weighing test. That was not a final finding of defamation.
Truth is not always a complete answer
Privacy law can apply even when every word is true. Ontario courts have recognized liability for intrusion upon seclusion (Jones v. Tsige, 2012 ONCA 32), public disclosure of private facts, and placing someone in a false light (Yenovkian v. Gulian, 2019 ONSC 7279). Sharing an intimate image without consent is also a crime under the Criminal Code.
Before you post about a real person
- Fact or opinion? If it is a fact, can you prove it with documents or witnesses?
- Firsthand or secondhand? Repeating what you heard carries the same risk as saying it yourself.
- Would a neutral reader identify them? If so, treat it as naming them.
- Is this the right audience? A complaint to an employer or regulator is often protected. The same words on public social media often are not.
- Does it include private details? Addresses, health, family, finances and images need a strong reason to share.
- Would a short delay hurt? If not, wait an hour and reread it.
If you are the one being defamed
Save the evidence with dates and URLs. Do not respond in kind. Get legal advice quickly: Ontario’s Libel and Slander Act imposes short notice periods for some publications, and general limitation periods still apply.
Sources
About Juliana Saxberg
Juliana Saxberg is an Ottawa lawyer, founder of Lex Artia Professional Corporation, and legal-tech commentator. Read her author profile →
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