- Canada has a single, unified self-defence provision — section 34 of the Criminal Code — since 2013 reforms replaced the old patchwork of overlapping sections.
- The test has three parts: a reasonable belief that force or a threat of force is being used, an act done for the purpose of defending against it, and a response that is reasonable in the circumstances.
- Reasonableness is assessed using a non-exhaustive list of factors — including imminence, other means available, any weapons involved, and the relative size and capabilities of those involved.
- Self-defence does not require a perfectly proportionate or minimal response — only a response that is reasonable given the whole context.
- Defence of property under section 35 is a related but separate provision, addressing protection of property rather than of a person.
- Once there is an “air of reality” to the defence based on the evidence, the burden shifts to the Crown, who must disprove self-defence beyond a reasonable doubt — it is never the accused's job to prove it.
The Short Answer
Yes — self-defence is a recognized, complete defence under Canadian criminal law, governed by section 34 of the Criminal Code. If the defence is properly raised on the evidence, the Crown must disprove it beyond a reasonable doubt. It is not something the accused has to affirmatively prove, and it does not require a perfectly measured or minimal response — only one that is reasonable given everything happening at the time.
A Single, Unified Provision: Section 34
Before 2013, Canada's self-defence law was spread across several overlapping and, at times, inconsistent sections of the Criminal Code, which had developed into a confusing and criticized area of law. The Self-Defence and Defence of Property reforms replaced that patchwork with a single, unified provision — section 34 — designed to apply consistently across the full range of self-defence situations, whether the force involved was minor or deadly, and whether the person was defending themselves or someone else.
The Three-Part Test
Section 34(1) sets out three elements that must all be present for the defence to apply:
The person believes, on reasonable grounds, that force is being used against them or another person, or that a threat of force is being made against them or another person.
The act that would otherwise be an offence is committed for the purpose of defending or protecting themselves, or the other person, from that use or threat of force.
The act committed is reasonable in the circumstances — assessed using a broad, non-exhaustive list of contextual factors, discussed below.
All three elements must be satisfied. The first is a subjective-but-grounded belief (the person must genuinely believe force was being used or threatened, and that belief must be reasonable, not fanciful). The second focuses on the purpose behind the act. The third is assessed objectively, based on the entire context.
What Makes a Response “Reasonable”?
Section 34(2) directs courts to consider the relevant circumstances of the person, the other parties, and the act itself, drawing on a non-exhaustive list of factors. Commonly considered factors include:
| Factor | What It Looks At |
|---|---|
| Nature of the force or threat | How serious or dangerous was the force or threat being responded to |
| Imminence | How close in time the threat was to materializing |
| Other means available | Whether there were realistic alternatives to responding with force |
| Role in the incident | The person's own conduct leading up to the confrontation |
| Use or presence of weapons | Whether any party used, or was known to have, a weapon |
| Size, age, gender, physical capabilities | The relative physical characteristics of those involved |
| Nature and proportionality of the response | How the act compares to the threat actually faced |
| Lawful force | Whether the act was in response to force the person knew was lawful |
A person is confronted by someone significantly larger who advances aggressively after making explicit threats of serious violence, with no realistic way to retreat. In that context, a forceful response that might look excessive in isolation can still be found reasonable, once the court weighs the imminence of the threat, the size disparity, and the lack of any safer alternative.
Reasonable Doesn't Mean Perfectly Proportionate
Canadian self-defence law does not require the person defending themselves to have measured out a perfectly calibrated, minimal response in the heat of the moment. The test asks whether the response was reasonable in the whole context — recognizing that people facing a genuine threat rarely have the luxury of calm, precise calculation.
This is one of the most misunderstood aspects of the law. People often assume self-defence requires matching force with force exactly, or using the absolute minimum force theoretically possible. That isn't the legal standard. Courts look at the situation as a whole, including the stress and uncertainty of the moment, when assessing whether the response was reasonable — not with the benefit of calm, after-the-fact hindsight.
Self-Defence vs. Defence of Property
Section 34 addresses defending a person — yourself or someone else — from force or a threat of force. A related but distinct provision, section 35, addresses defence of property: protecting property you are in peaceable possession of from someone who is entering it, taking it, or damaging it without entitlement. Defence of property has its own specific elements and its own assessment of reasonableness, and the two defences, while conceptually similar, are not interchangeable — a case involving a confrontation over property may raise issues under both sections depending on exactly what happened.
Who Has to Prove What
Self-defence is not something the accused has to affirmatively prove. Once there is an “air of reality” to the defence — meaning the evidence provides a genuine evidentiary basis on which a properly instructed jury or judge could find the elements are met — the burden shifts to the Crown. From that point forward, the Crown must disprove self-defence beyond a reasonable doubt, the same high standard that applies to every other element of a criminal charge.
Practically, this means the defence does not need to be established with certainty, or even on a balance of probabilities. Once the air of reality threshold is met — based on the whole of the evidence, whether it comes from the accused, other witnesses, or the surrounding circumstances — the accused is entitled to an acquittal unless the Crown can eliminate any reasonable doubt that the defence applies.
Common Myths
Myth: “You have to use the exact same weapon or force level used against you.”
False. The law requires a reasonable response in the whole context, not an exact match in force or method.
Myth: “You have to prove you acted in self-defence.”
False. Once the defence has an air of reality on the evidence, the Crown bears the burden of disproving it beyond a reasonable doubt.
Myth: “If you started the argument, you automatically lose the right to self-defence.”
Not automatically. A person's role in the incident is one relevant factor among several, not an absolute bar to raising the defence.
Facing charges arising from a situation where you believe you acted in self-defence? Call our Toronto criminal defence lawyers at 416-274-2222 for a free consultation.
Frequently Asked Questions
Section 34 of the Criminal Code, following the 2013 Self-Defence and Defence of Property reforms that replaced the previous patchwork of multiple overlapping self-defence sections with a single, unified provision.
A three-part test under section 34(1): the person must believe on reasonable grounds that force or a threat of force is being used against them or someone else, the act must be done for the purpose of defending or protecting themselves or the other person from that force, and the act itself must be reasonable in the circumstances.
No. Canadian law does not require a perfectly proportionate or minimal response — it requires a response that is reasonable given the whole context, including factors like the nature of the threat, whether other options were realistically available, and the relative size and capabilities of those involved.
Section 34(2) sets out a non-exhaustive list, including the nature of the force or threat, how imminent it was, whether other means of responding were available, the history and nature of any relationship between the parties, whether anyone used or threatened to use a weapon, the size, age, gender, and physical capabilities of those involved, and the proportionality of the response to the threat faced.
No. Once there is an "air of reality" to the defence — meaning there is some evidentiary basis on which a properly instructed jury or judge could conclude the defence applies — the burden shifts to the Crown, who must then disprove self-defence beyond a reasonable doubt. It is never the accused's job to prove they acted in self-defence.
Self-defence, under section 34, concerns protecting a person from force or a threat of force. Defence of property, under section 35, is a related but separate provision addressing the protection of property someone is in peaceable possession of, and it has its own specific requirements.
It can be more difficult, since a person's role in the incident is one of the factors a court considers in assessing reasonableness, but it does not automatically disqualify the defence. Every case depends on the specific facts, including how the confrontation escalated and what happened at the relevant moment force was used.
Yes. Section 34 explicitly covers force used to defend or protect either yourself or another person from force or a threatened use of force.
It depends entirely on the surrounding circumstances. The presence or absence of weapons is one of the specific factors considered in assessing reasonableness, alongside the relative size, capabilities, and the nature of the threat faced — it is not an automatic bar to the defence.
Yes, strongly. How the facts are described early on can significantly affect how the case develops. Speaking to a lawyer first, even briefly, helps ensure your account is presented accurately and in a way that properly reflects the legal test.