Mistaken Identity Arrests: When Police Errors Infringe Rights
A recent decision from the Court of Appeal for Ontario, R v TG, 2026 ONCA 298, confirms that when police arrest the wrong person by mistake, that arrest may be unlawful — and any evidence police find as a result may be thrown out at trial.
What Happened
The case involved a mistaken identity arrest. Police had legal grounds to arrest a specific individual. But when they moved in, they arrested that person's brother instead. While carrying out the arrest, officers searched him and found a firearm and drugs. He was charged based on what was discovered during that search.
The question for the Court of Appeal was whether the arrest itself was legal — and if not, whether the firearm and drugs could still be used as evidence against him.
The Legal Background: Two Kinds of Police Mistakes
To understand the decision, it helps to know how Canadian law treats police errors in the arrest context.
Section 9 of the Canadian Charter of Rights and Freedoms protects everyone against "arbitrary" detention or arrest. In plain language, this means police can't lock you up on a hunch or without a proper legal basis. They need real grounds to arrest you.
But what happens when police think they have grounds — and they're wrong? The law distinguishes between two types of mistakes:
Mistakes of law — where police misunderstand what the law actually says. The Supreme Court of Canada has held that an arrest based on a misunderstanding of the law is always unlawful and breaches section 9.
Mistakes of fact — where police have the law right but get the underlying facts wrong, such as arresting the wrong person, or believing someone is committing an offence when they are not.
Until TG, the rules around mistake-of-fact arrests were less settled in Ontario.
What the Court Decided
The Court of Appeal held that an arrest based on a factual mistake can still be legal — but only if the mistake was reasonable in the circumstances. An unreasonable mistake makes the arrest unlawful and triggers Charter protections.
In TG's case, the Court found that the police error was objectively unreasonable for three reasons:
The officers had only a poor opportunity to observe him before making the arrest.
There were visible differences in appearance between the person they intended to arrest (the brother) and the person they actually arrested.
Police failed to take readily available steps to verify his identity before completing the arrest.
Because the mistake was unreasonable, the arrest violated section 9 of the Charter. The majority of the Court excluded the firearm and the drugs from evidence and entered acquittals.
Why This Decision Matters
TG clarifies that the standard for a lawful arrest is flexible and fact-specific, but it is not unlimited. Police can't act on superficial impressions when better information is within reach. When the circumstances allow for verification — and especially when warning signs suggest something might be off — officers are expected to take reasonable steps to confirm they have the right person before depriving them of their liberty.
As the Court put it, in some cases it will be "incumbent upon the police to make further inquiries or observations before effecting an arrest." When police fail to act with that kind of restraint, the evidence they subsequently find may be excluded from the trial.
This is a meaningful protection. Wrongful arrests cause real harm — to reputations, employment, family relationships, and to the public's trust in the justice system. TG reinforces that the Charter takes those harms seriously.
What This Means for You
If you have been arrested and you believe police arrested the wrong person, or made another significant factual error, that mistake may have legal consequences for your case. An arrest based on an unreasonable factual mistake can amount to a breach of your Charter rights, and any evidence police discover during or after that arrest — including weapons, drugs, statements, or other items — may be excluded from your trial.
Some questions a defence lawyer will ask in this kind of situation include:
How clearly did police actually see or identify you before making the arrest?
Were there obvious differences in your appearance compared to the person they were looking for?
Did police take simple, available steps to verify your identity — for example, asking your name, checking ID, or running a quick database search?
Did you try to clarify the situation, and did police listen?
Every case turns on its own facts, and not every police error will lead to a Charter remedy. But if you have concerns about how an arrest was carried out, an experienced criminal defence lawyer can review the circumstances and advise you on whether the evidence against you may be challenged.
If you or a family member is facing charges arising from a questionable arrest, contact us to discuss your options.