Mistake of Fact and Mistake of Law
- Lesson 10 of 24
- Core
- Mistake of Fact vs Law (ss. 19-20). Mistake of fact negating subjective mens rea vs ignorance of the law and official induced error.
- 12 min
- Reviewed
By James R. GosnellEducational material, not legal advice.
Key points
A factual mistake affects proof of fault under the offence’s applicable standard and statutory limits, including those governing consent and age. Ordinary legal ignorance does not excuse an offence, while officially induced error requires six conditions and leads to a stay of proceedings.
The lesson's scenario
Taking the Wrong Station Bag vs. Honest Belief in a Private Sale Agreement
Go to the worked example- Builds on
- Lesson 9 set the procedural architecture: how defences are screened and who bears the burden of proof.
- This lesson
- Mistake of fact negating mens rea, ignorance of the law (s. 19), colour of right in property offences, mistaken belief in communicated consent (s. 273.2), and officially induced error.
- Leads to
- Lesson 11 examines other critical defence issues that challenge guilt: consent, chronological age, alibi, prank, and accident.
A three-pass reading method
- Start with the worked example. Seeing the facts first anchors the abstract rules.
- Read the doctrine: the statutory elements, the fault standard and the leading cases. Note the tests judges apply.
- Finish with the practice checklist and the recall cards at the end of the lesson.
Overview
An error is legally relevant only when connected to the offence or a recognized excuse. A sincere belief does not automatically defeat every charge. Begin by identifying what the accused believed, which element it affects, and the applicable fault standard. JurisClasseur Québec, Droit pénal général, fascicule 14 follows these distinctions.
Section 19 of the Criminal Code states the general rule that ignorance of the law does not excuse an offence. Specific statutory language and the doctrine of require separate consideration.
Learning Objectives
- Connect a claimed factual mistake to the offence's actual fault requirement.
- Apply the statutory limits on mistaken consent and age without reversing the Crown's burden.
- Distinguish colour of right and officially induced error from ordinary legal ignorance.
Fact, law and the applicable burden
A concerns the factual situation. A concerns the meaning or legal consequences of facts the accused knows. Mixed questions require careful analysis; changing the label does not turn a mistaken interpretation of the prohibition into a factual defence (nos 1–3).
| Fault regime | Effect of a factual mistake |
|---|---|
| An honest mistake may raise a reasonable doubt about the required intention or knowledge, subject to statutory restrictions. Its reasonableness is evidence bearing on whether it was actually held. | |
| An honest and reasonable mistake is relevant to assessing the conduct. The Crown must still prove the required departure from the standard of care. | |
| An honest and reasonable factual mistake, or due diligence, must be established by the defendant on a balance of probabilities. | |
| Absolute liability | An absence-of-fault defence based on the mistake is unavailable; the material elements and other applicable defences remain distinct. |
A failure to establish a reasonable mistake does not automatically establish a marked departure in an objective-fault prosecution. The court must assess all the evidence under the offence's actual standard (nos 18–23).
Wilful blindness cannot be recast as innocent ignorance. Recklessness involves actual awareness of a risk; a mistake that leaves that awareness intact does not negate it. Conversely, a genuine factual error may matter if it prevents the relevant awareness (nos 12–16).
Intoxication requires care. A mistake caused by self-induced intoxication cannot ordinarily defeat general intent, whereas evidence affecting specific intent may be relevant. A person who was intoxicated is not automatically barred from relying on an independently arising mistake they would also have made sober. Extreme intoxication and section 33.1 are addressed separately in the intoxication lesson (no 17).
Worked example: taking the wrong bag
Factual Scenario
In this hypothetical, Nora takes a bag from a station believing it is hers. Its colour and luggage tag resemble her own. Compare her position with Malik, who knows which bag he takes but honestly believes that its owner transferred ownership to him under a sale agreement. The agreement and prior messages support that belief, although the supposed transfer is legally ineffective. Both face a theft allegation. Identify the kind of error and the burden in each case.
Nora alleges a factual error about the bag's identity. If honestly held, it can raise a reasonable doubt about the fault required for theft. The resemblance supports sincerity without making an objectively reasonable mistake an independent general requirement for subjective fault.
Malik alleges colour of right based on a private-law entitlement. He need not prove that the transfer was legally effective: the relevant issue is his honest belief in that entitlement, assessed under the offence's requirement of absence of colour of right. The agreement and messages provide evidence of his state of mind. The Crown must prove the required absence of colour of right beyond a reasonable doubt; it cannot obtain conviction merely by winning the civil-law issue about ownership. Neither person bears a general balance-of-probabilities burden to establish innocence ( and 80–85).
Variation
Malik instead admits that he knew he had no legal entitlement to the bag. He took it because its owner owed him money and he considered self-help morally deserved. Does sincerity alone establish colour of right?
The asserted belief concerns moral entitlement despite the law, rather than an honestly perceived private-law right. It does not establish colour of right merely because Malik sincerely considered the taking fair. A genuine, even legally mistaken, belief in a particular civil right would require separate examination; an unpaid debt alone cannot supply that belief or authorize every means of collection. The Crown must still prove the other theft elements.
Mistaken belief in communicated consent
For sexual assault, actual consent and the accused's belief are separate questions. Actual consent is the complainant's voluntary agreement to the sexual activity in question. The mental element concerns intentional touching and knowledge, recklessness or wilful blindness concerning non-consent (nos 24–34).
The relevant claim is an honest but mistaken belief in , not a belief that the law treats silence or previous sexual activity as permission. Communication may be by words or conduct. There must be an evidentiary basis for the alleged communication, and under paragraph 273.2(b) must have been taken in the circumstances known at the time (nos 35–48.1).
The Code bars reliance on beliefs arising from self-induced intoxication, recklessness or wilful blindness, as well as the other statutory exclusions. Silence, passivity, ambiguous behaviour, a general advance permission or a supposed propensity to consent cannot supply the missing legal foundation. Consent to earlier activity does not settle agreement to the activity now in question.
Reasonable steps are contextual; the law does not impose a single verbal script for every encounter. Intoxication, ambiguity, risk and indications of non-consent can demand further inquiry. The requirement concerns reasonable steps, rather than simply substituting a freestanding requirement that every mistaken belief be objectively reasonable (nos 35–48.1).
If the claim lacks an air of reality, it is not left with the trier of fact. That does not by itself direct a conviction: the Crown must still prove all elements of the offence beyond a reasonable doubt (nos 49–51).
Worked example: agreement and communicated consent
Factual Scenario
In this hypothetical, Anouk and Jules are adults, sober and capable of consenting. Anouk agrees to kissing but testifies that she never agreed to Jules touching her breast. She says she heard him ask whether he could sit closer and replied yes. Jules testifies that he specifically asked whether he could touch her breast and understood her yes as permission for that touching. Neither alleges threats or incapacity. Assume the trier of fact accepts that Anouk did not actually agree to the touching. Determine whether that finding resolves the offence and identify the evidence relevant to Jules's claimed belief.
The actual-consent inquiry concerns Anouk's voluntary agreement to the particular activity at the time. Her agreement to kissing does not supply agreement to the other touching. On the stated finding, absence of actual consent is established; Jules's perception cannot replace her state of mind. This is the first part of the analysis explained in the consent lesson.
The mental-element inquiry then considers Jules's intentional touching and knowledge, recklessness or wilful blindness concerning non-consent. His precise account of a question and answer provides evidence of what he says was communicated. If reasonably capable of belief, it can support an honest mistaken belief and an inquiry into reasonable steps. A specific request directed to the particular touching differs from relying on prior kissing. The judge must assess whether the record supports each required component before leaving the claim with the trier of fact.
The conflicting testimony does not mandate conviction or establish the defence. The fact-finder must evaluate whether Jules honestly held the alleged belief, what steps he took in the circumstances known to him, and whether an exclusion applies, while retaining the Crown's ultimate burden. Anouk's actual non-consent and Jules's possible factual mistake are legally distinct; the court cannot manufacture a coherent mistaken-belief account by combining evidence that cannot reasonably fit together ( and 49–52).
Variation
Both now agree that Anouk answered the specific request with no, and Jules continued because she had previously agreed to kissing. What changes?
The alleged permission now rests on substituting prior activity for communicated agreement despite an express refusal. Those facts do not support an honest mistaken belief in communicated consent to the touching. Proceeding after the refusal supplies evidence of the required mental element, subject to the Crown proving the complete offence beyond a reasonable doubt. The error is not repaired by calling the earlier kissing a reasonable step.
Mistaken age
The age rules for the charged offence must be identified first, including any applicable close-in-age exception. Section 150.1 contains specific restrictions on an alleged belief that the complainant had reached the relevant age. The required standard is all reasonable steps, not every imaginable inquiry (nos 52–62).
Appearance or an assertion of age is not invariably sufficient; the whole context matters. The requirement for all reasonable steps is substantive, but it does not make the accused prove the mistake on a balance of probabilities. JurisClasseur distinguishes the evidential foundation from the Crown's ultimate burden (nos 54–55).
The obligation continues when new facts arise. In a hypothetical ongoing relationship, an initial account of age may have seemed credible, but a later message identifying a different birth year requires the accused to address that information. Simply repeating the earlier assertion ignores the changed circumstances. The necessary further inquiry depends on what the accused knows and what would reasonably resolve the inconsistency; there is no universal number of checks. A steps analysis must therefore identify both the information available before the activity and any renewed reason for inquiry (nos 56–62).
Mistake of law and colour of right
An ordinary misunderstanding of a criminal prohibition falls under section 19. A sincere view that the law is unfair, invalid or should not apply is not a personal exemption. In strict liability, a legal mistake is not transformed into due diligence by showing good faith (nos 76–79).
Some offence definitions make beliefs about private-law rights relevant, notably in property matters and certain family-law contexts. Where absence of colour of right is an element, apply the following distinctions (nos 80–85):
- The asserted entitlement concerns civil or private law. Believing that criminal law does not prohibit the act, or that morality justifies defying the law, does not establish the same claim.
- The accused must actually and honestly believe in the entitlement. A right they might have believed in is insufficient. The belief can be legally unfounded; the criminal court need not uphold it as a valid civil right.
- The test is subjective. Unreasonableness can undermine the credibility of the alleged belief, without automatically defeating an honestly held claim.
- The Crown must establish absence of colour of right beyond a reasonable doubt where the offence requires it. A supported reasonable doubt on that element suffices; the accused need not prove the claimed right on a balance of probabilities.
The particular provision controls the claim's scope. The bag exercise illustrates why private-law belief, factual mistake and moral self-help must be separated; none creates a general permission to use unlawful means to collect a debt.
A factual mistake can also support a separate defence. For self-defence, for example, the perceived use of force must have a reasonable foundation under that defence's own requirements. The subjective-fault row in the earlier table cannot eliminate that condition. Apply the self-defence test to the perceived circumstances (nos 63–64).
Officially induced error
JurisClasseur presents the six conditions recognized in Lévis (City) v. Tétreault, 2006 SCC 12:
- An error of law or mixed law and fact occurred.
- The accused considered the legal consequences of the proposed act.
- Advice was obtained from an appropriate official.
- The advice was reasonable in the circumstances.
- The advice was erroneous.
- The accused acted in reliance on it.
The official must be appropriate to the law and issue in question. Private legal advice does not, simply because it comes from a qualified lawyer, satisfy that requirement. The source also describes limits and uncertainty concerning advice from particular officials; official employment alone is insufficient (nos 94–104).
The accused bears the balance-of-probabilities burden on this excuse. Preserve the question asked, facts disclosed, advice given, official's role and evidence of actual reliance. Passive assumption or the authorities' mere tolerance of known illegality is not the same as obtaining and relying on qualifying advice. If the excuse is established, the remedy is a stay of proceedings, not an acquittal for absence of mens rea (nos 90–109).
Practice Checklist
- State the exact factual or legal belief alleged and the element it affects.
- Identify the fault regime and the correct burden.
- Examine knowledge, recklessness, wilful blindness and the role of intoxication.
- For consent or age, apply the relevant reasonable-steps rule and statutory exclusions.
- Test a claim of right against the particular offence, not a general sense of entitlement.
- For officially induced error, prove each condition and request the correct remedy.
Check your understanding
Two short exercises before you move on: reason through the lesson’s worked examples, then recall its key terms from memory.
Apply the rules
Each worked example gives the facts first and keeps its analysis closed. Decide the outcome, then open the analysis to compare.
Active recall
1 / 8Formulate your answer before revealing the definition. Your self-assessment schedules a review; it does not measure mastery.
mistake of fact
erreur de fait
How would you define this concept? Which conditions or limits matter?
Glossary
- communicated consentconsentement communiqué
- Consent expressed through words or conduct; an accused’s alleged belief must concern communication of agreement to the sexual activity in question.
- mistake of facterreur de fait
- A mistaken belief about material facts that may negate the fault required for the offence.
- mistake of lawerreur de droit
- A mistake about the legal meaning or consequences of facts; ordinarily no excuse under section 19.
- Objective penal faultFaute pénale objective
- A fault regime requiring the Crown to prove the applicable departure from the standard of care, with an honest and reasonable mistake relevant to the assessment.
- officially induced errorerreur provoquée par une personne en autorité
- An excuse requiring proof of the six conditions concerning erroneous legal advice from an appropriate official and reliance on that advice.
- Reasonable stepsMesures raisonnables
- Contextual inquiries required for a mistaken belief in consent; the distinct age provisions require all reasonable steps.
- Strict liabilityResponsabilité stricte
- A fault regime in which the defendant must establish an honest and reasonable factual mistake or due diligence on a balance of probabilities.
- Subjective faultFaute subjective
- A fault regime in which an honest factual mistake can raise a reasonable doubt about the required intention or knowledge, subject to statutory limits.
References and Further Reading
- Primary source: JurisClasseur Québec, Droit pénal général, , “Erreur”, nos 1–114; merged PDF pp. 541–597.
- Legislation discussed in the source: Criminal Code, ss. 19, 150.1, 273.1–273.2 and the relevant offence-specific claim-of-right provisions.
- Cases discussed in the source: Pappajohn, [1980] 2 SCR 120; Sansregret, [1985] 1 SCR 570; Briscoe, 2010 SCC 13; Barton, 2019 SCC 33; Lévis (City) v. Tétreault, 2006 SCC 12.