Few parts of investigation law generate more confusion than recording. People tend to assume either that all secret recording is illegal, or that none of it is. The reality sits in between, and it is set by federal criminal law: Part VI of the Criminal Code, which applies in Ontario as it does across Canada. The rule it establishes is commonly called one-party consent. This page explains the rule, what it permits, what remains illegal, and the practical caveats that matter as much as the rule itself. It is general information, not legal advice.
The one-party consent rule
The Criminal Code makes it an offence to wilfully intercept a private communication; section 184 carries a penalty of up to five years’ imprisonment. The same provision contains the exception that gives the rule its name: interception is not an offence where one of the parties to the communication, its originator or its intended recipient, has consented to it.
In plain terms: if you are a party to a conversation, you may lawfully record it, and you do not need the other side’s permission or knowledge under the criminal law. There is no separate Ontario rule that changes this; recording law in this respect is federal and uniform across the country.
What the rule permits
You may record your own phone calls, meetings, and conversations, because you are a party and your own consent satisfies the exception. The rule cuts both ways: the people you speak with may lawfully record you on the same footing, announced or not.
One distinction is worth drawing early. An individual recording their own conversations is in different territory from an organization recording customers or staff. Organizations collecting personal information operate under PIPEDA’s consent and transparency obligations, which is a separate layer on top of the criminal-law rule; we set out that framework in PIPEDA and lawful surveillance.
What stays illegal
The exception applies only to a party to the communication. Recording a conversation you are not part of is interception, and it is a crime. That covers the classic cases: a device left running in a room you then leave, a tap on someone else’s line, a hidden microphone, accessing another person’s calls, voicemail, or messages without authority. It does not matter whose house, whose spouse, or whose employee is involved; being close to a conversation is not the same as being a party to it.
This is also where recording law meets counter-surveillance. A planted listening device is not a grey area. It is the offence itself, which is why finding one matters and why we treat a located device as evidence. We explain that discipline in how a professional bug sweep actually works. And as with every limit on this site’s legal pages, recording in places where a person has a reasonable expectation of privacy, such as inside a home, a bathroom, or a change room, is off-limits regardless of consent rules about conversation.
Lawful is not the same as usable, or wise
The one-party rule answers a criminal-law question. It does not answer the questions that usually matter next. Courts and tribunals can view surreptitious recordings critically, particularly in family matters, and they weigh how a recording was obtained and whether it is complete alongside what it contains. A fragment that captures the worst thirty seconds of a long conversation invites the argument that context was removed, the same completeness principle that governs surveillance evidence generally. Authenticity has to be demonstrable. And a recording made lawfully can still be handled badly: shared where it should not be, or relied on in place of the record a decision-maker would actually credit.
This is why professional practice is more conservative than the law requires. A licensed investigator does not intercept private communications, and surveillance video is generally captured without audio for exactly this reason. Documentation is built from what is lawfully observable, the standard we describe in what a PI can and can’t do.
If your concern runs the other way, that someone may be recording you unlawfully, that is a specific, articulable concern, and it is the situation a technical surveillance countermeasures examination exists to resolve.
Not legal advice
This page is general information about Canadian law and is not legal advice. Whether a specific recording was lawful, and what weight it would carry, depends on the facts and the venue; consult a lawyer for a specific situation.