Anti-SLAPP Motions in Ontario: How Courts Dismiss Defamation Claims That Silence Speech

Some defamation lawsuits are not really about seeking justice — they are about making the speaker pay enough in legal fees to go quiet. A business suing a whistleblower. A politician suing a critic. A developer suing residents who opposed a project. Ontario law calls these SLAPPs — Strategic Lawsuits Against Public Participation — and the Courts of Justice Act gives defendants a powerful tool to shut them down before trial.

If you have been sued for something you said or published, an anti-SLAPP motion may let you end the case early and recover your legal costs. If you are considering suing someone for a public statement, understanding the anti-SLAPP risk is essential before you file anything.

What Is a SLAPP?

SLAPP stands for Strategic Lawsuit Against Public Participation. These are lawsuits — usually framed as defamation, but sometimes as other torts — brought primarily to intimidate, exhaust, or silence critics, rather than to vindicate a genuine legal right.

Classic SLAPP scenarios:

• A corporation sues an individual who posted critical comments about the company's environmental practices.
• A landlord sues a tenant who complained publicly to the city about building conditions.
• A public figure sues a journalist or blogger who covered their conduct critically.
• A business sues a former customer who left a scathing review.

In all of these, the legal claim may have surface plausibility, but the underlying goal is to use litigation costs and stress to make the speaker recant, remove the statement, or simply stop speaking.

Ontario's Anti-SLAPP Framework

Ontario amended the Courts of Justice Act to add a specific mechanism to dismiss such claims. The framework operates as a motion to dismiss, heard on an expedited basis, with the following key features:

Step 1: The defendant brings the motion

A defendant who believes the claim against them arises from an expression relating to a matter of public interest can bring a motion to dismiss under the Courts of Justice Act. There is a deadline to bring this motion — verify the current procedural timeline with a lawyer, as it must generally be brought before specific steps in the litigation, and courts have interpreted the timing rules strictly.

Step 2: Proceedings are stayed

Once the motion is brought, the rest of the litigation is stayed — discovery, examinations, and other steps halt. This protects the defendant from being buried in litigation costs while the motion is pending.

Step 3: The burden-shifting test

The motion involves a two-stage analysis:

First, the defendant must show that the proceeding arises from an expression that relates to a matter of public interest. Courts have interpreted "public interest" broadly — it includes commercial matters, online reviews, local government decisions, professional conduct, and much more.

If the defendant meets this threshold, the burden shifts to the plaintiff, who must satisfy the court of two things:

1. Grounds to believe the proceeding has substantial merit — the claim must have real legal substance, not just surface plausibility.
2. Grounds to believe the defendant has no valid defence — the plaintiff must show the defendant cannot reasonably succeed with truth, fair comment, privilege, or another defence.

Then the court weighs harm: Even if the plaintiff satisfies the above, the court must be satisfied that the harm caused by the defendant's expression is sufficiently serious that the public interest in allowing the proceeding to continue outweighs the public interest in protecting the expression.

If the plaintiff cannot satisfy all of these requirements, the motion succeeds and the claim is dismissed.

The Cost Consequence: Why Anti-SLAPP Is Powerful

The costs rules on an anti-SLAPP motion are deliberately severe:

• If the motion succeeds, the plaintiff must pay the defendant's costs on a full indemnity basis — meaning the actual, reasonable legal fees the defendant incurred, not the partial recovery typical in Ontario civil litigation.
• If the motion fails, the defendant pays the plaintiff's costs on the same full indemnity basis.

This symmetry is intentional. Full indemnity costs are a major deterrent against bringing a SLAPP lawsuit in the first place, because the downside of losing the motion can be financially devastating.

Who Can Use the Anti-SLAPP Provisions?

The anti-SLAPP provisions are available to any defendant in a proceeding that arises from expression on a matter of public interest. You do not need to be a journalist or a major public figure. Individuals who:

• Posted online reviews
• Shared opinions on social media about a local business or institution
• Complained to a regulatory body or government office
• Wrote publicly about their personal experience with a company or professional
• Participated in community opposition to a project

…may all be able to use the anti-SLAPP provisions if they are subsequently sued.

What Counts as a "Matter of Public Interest"?

Courts have defined "public interest" broadly. It does not mean "of interest to the general public" in a mass-media sense. It can include:

• The conduct of businesses and professionals who serve the public
• Consumer experiences with products or services
• Local development and land-use issues
• The conduct of public figures in their public roles
• Environmental, health, or safety concerns

Courts look at whether the expression concerned an issue that goes beyond purely private matters between the parties.

For Plaintiffs: The Anti-SLAPP Risk Assessment

If you are considering a defamation lawsuit, the existence of anti-SLAPP provisions should be a central part of your pre-filing risk assessment. Ask your lawyer:

• Is this claim likely to be characterized as arising from an expression on a matter of public interest?
• Can I demonstrate substantial merit and the absence of a credible defence?
• Is the harm I suffered serious enough to survive the court's weighing exercise?
• What is the exposure if the anti-SLAPP motion succeeds and I owe full indemnity costs?

A claim that you might win at trial can still be strategically dangerous if the defendant can bring a successful anti-SLAPP motion and leave you with a large costs order before trial even begins.

Frequently asked questions