- Ontario recognizes two distinct civil claims in this area: false arrest/false imprisonment, and malicious prosecution — each with its own legal test.
- A false arrest claim focuses on whether the arrest itself was lawful — generally, whether police had reasonable grounds to arrest at the time.
- Malicious prosecution requires proving four elements: the defendant initiated the prosecution, it terminated in the plaintiff's favour, there was a lack of reasonable and probable grounds, and the defendant was motivated by malice.
- Under Miazga v. Kvello Estate, 2009 SCC 51, a prosecutor does not need a subjective belief in guilt, and malice cannot be presumed simply from a lack of reasonable grounds.
- Malice requires proof of an improper purpose — negligence, poor judgment, or even gross negligence is not enough on its own to establish it.
- These are genuinely difficult claims to win, deliberately so, to avoid discouraging police and prosecutors from doing their jobs.
The Short Answer
Yes, it is possible to sue for wrongful arrest or malicious prosecution in Ontario — but both claims are deliberately difficult to win. Being arrested and later cleared, or having charges withdrawn, does not automatically entitle you to sue. Each claim has its own demanding legal test, examined below.
Two Distinct Claims
Ontario law recognizes two separate civil claims in this area, and it's important not to confuse them:
- False arrest / false imprisonment — focused on whether the arrest and detention itself was lawful
- Malicious prosecution — focused on whether the decision to prosecute was made without reasonable grounds and with an improper purpose
False Arrest / False Imprisonment
This claim centres on whether the arresting officer had reasonable grounds to make the arrest at the time — generally the same standard police must meet under the Criminal Code to lawfully arrest someone. If an arrest was made without the required reasonable grounds, it can potentially support a false arrest claim, regardless of how the underlying criminal matter later turned out.
Malicious Prosecution: The Four Elements
Malicious prosecution is a distinct, more demanding claim, requiring proof of four elements:
- The prosecution was initiated by the defendant
- The prosecution terminated in the plaintiff's favour (such as an acquittal or withdrawal of charges)
- There was a lack of reasonable and probable grounds to commence or continue the prosecution
- The defendant was motivated by malice in commencing or continuing it
Why Malicious Prosecution Is Genuinely Hard to Prove
The leading case, Miazga v. Kvello Estate, 2009 SCC 51, significantly clarified — and raised — the bar for these claims:
The Supreme Court held there is no requirement for a prosecutor to have a subjective belief that the accused is actually guilty, and — critically — malice cannot simply be presumed from a lack of reasonable and probable grounds. The two elements must be proven separately.
Malice requires proof of an improper purpose, inconsistent with the proper role of the prosecutor's (or other defendant's) office. Importantly, the Court confirmed that none of the following are enough on their own to establish malice: incompetence, inexperience, poor judgment, laziness, recklessness, an honest mistake, negligence, or even gross negligence.
Who Can You Sue?
Depending on the specific facts, a claim might be brought against the police officers involved in an arrest, or against Crown prosecutors involved in a decision to prosecute — though Crown prosecutors benefit from certain recognized protections given the nature of their public role, making claims against them particularly demanding.
What Damages Are Available
- Compensation for the deprivation of liberty during any detention
- Reputational harm
- Legal costs incurred defending the underlying criminal charge
- Lost income
- Emotional distress, where properly established
Common Mistakes
This satisfies only one of the required elements for malicious prosecution — the other three, including malice, still need to be proven.
Even a poorly handled prosecution does not amount to malice on its own — an improper, bad-faith purpose must be shown.
These are separate legal claims with different tests — conflating them weakens your case's framing.
Limitation periods apply to civil claims — don't assume you have unlimited time to pursue this after your criminal matter concludes.
Believe you were wrongfully arrested or maliciously prosecuted? Call our Toronto team at 416-274-2222 for a free, honest consultation.
Frequently Asked Questions
Not automatically — charges being withdrawn or an acquittal is one element of a malicious prosecution claim, but far from the whole test. You would still need to establish that the prosecution was initiated by the defendant, that there was a lack of reasonable and probable grounds, and that the defendant acted with malice.
False arrest (or false imprisonment) focuses on whether the arrest and detention itself was lawful — generally, whether police had reasonable grounds to arrest at the time. Malicious prosecution is a separate claim focused on whether the decision to prosecute was made without reasonable grounds and with an improper, malicious purpose.
Four elements must be proven: the prosecution was initiated by the defendant; it terminated in the plaintiff's favour; there was a lack of reasonable and probable grounds to commence or continue the prosecution; and the defendant was motivated by malice in commencing or continuing it.
No — the Supreme Court in Miazga v. Kvello Estate confirmed there is no requirement for a prosecutor to have a subjective belief in the accused's guilt. The relevant question is whether reasonable and probable grounds existed, not what the prosecutor personally believed.
No. The Supreme Court specifically held that malice cannot be presumed simply from a lack of reasonable and probable grounds — malice requires separate, affirmative proof of an improper purpose.
Malice requires proof that the prosecutor (or other defendant) was acting for an improper purpose, inconsistent with the proper role of their office — not merely incompetence, inexperience, poor judgment, laziness, recklessness, an honest mistake, or even negligence or gross negligence, none of which are enough on their own.
The legal tests differ somewhat depending on who is being sued and the specific claim. Crown prosecutors benefit from certain protections recognized in the case law given the nature of their public role, while claims against police for the arrest itself focus more directly on whether reasonable grounds existed at the time of arrest.
Potential damages can include compensation for the deprivation of liberty, reputational harm, legal costs incurred defending the criminal charge, lost income, and emotional distress, depending on the specific facts and losses proven.
The bar is set deliberately high to avoid discouraging police and prosecutors from doing their jobs — the justice system depends on officials being able to make good-faith arrest and prosecution decisions without constant fear of civil liability for honest mistakes or reasonable judgment calls that don't pan out.
Strongly recommended, and close to essential. These are complex, fact-intensive claims with a demanding legal test, and a lawyer experienced in this specific area can help you realistically assess whether your situation actually meets the bar before investing significant time and resources.