Preliminary Considerations in Criminal Defences

Overview

Before applying a defence, identify what it does and who must prove the relevant issue. Some arguments challenge an element the Crown must establish. Others justify or excuse the conduct, reduce the offence, produce a special verdict or support a procedural remedy. The word defence does not determine either the burden of proof or the outcome.

Learning Objectives

• Distinguish denial of an offence element, justification, excuse and procedural remedy.
• Separate an evidential foundation from the ultimate burden of persuasion.
• Identify the proper outcome and the particular rules governing the proposed defence.

Identify the Legal Function

Elements, justifications and excuses

An alibi challenges participation. A relevant factual mistake may prevent proof of the mental element. An accident may challenge voluntary conduct, fault or a required consequence, depending on what was accidental. These arguments do not permit skipping the offence's exact elements or its applicable fault standard.

Self-defence can justify otherwise prohibited conduct when its conditions are met. Necessity and duress address constrained choices under their particular rules. The distinction between justification and excuse helps explain their rationale, but the actual legal conditions still control. Moral involuntariness under necessity or duress differs from physical involuntariness in automatism.

Outcomes differ

Successful self-defence ordinarily results in acquittal. Provocation is a partial defence to murder that can reduce it to manslaughter; it does not generally excuse assault or require complete acquittal. The section 16 mental-disorder defence produces a special verdict of not criminally responsible on account of mental disorder when established. Entrapment ordinarily supports a stay after guilt has been determined. An officially induced error of law likewise has its own conditions and stay remedy.

Failure of one defence does not prove the charge. The Crown must still establish the offence, and any other properly supported issue must be resolved under its own rules.

Sources and Scope

Statutory and common-law rules

Start with the offence and any express defence. Section 8(3) of the Criminal Code preserves common-law justifications, excuses and defences except where legislation alters them or makes them inconsistent. A general common-law principle cannot be used to erase an applicable statutory restriction without the necessary legal analysis.

In Quebec provincial penal proceedings, article 60 of the Code of Penal Procedure makes relevant criminal defences and justifications available with necessary adaptations and subject to its terms. This does not import every procedure or supervisory disposition in Part XX.1 of the Criminal Code. The Patry discussion in JurisClasseur illustrates that distinction for mental disorder.

Regulatory classification also matters. Strict liability permits due diligence; absolute liability excludes that defence but does not automatically eliminate challenges to the actus reus or every general defence. Identify the precise statute and argument.

Burdens of Proof

The ordinary rule

The Crown ordinarily proves the offence beyond a reasonable doubt. For most defences, the record must first provide a sufficient evidential foundation. Once a defence is properly in issue, the Crown must disprove it beyond a reasonable doubt. It can do so by disproving a required condition; it need not disprove every condition separately.

The supporting evidence may come from prosecution witnesses or other admissible evidence. The accused need not invariably testify or call a defence witness. Where the Crown bears the burden of disproving a properly raised complete defence, a reasonable doubt requires acquittal of the affected charge. That rule does not replace an exceptional persuasive burden imposed on the accused, and a partial defence has a different consequence.

Exceptional persuasive burdens

Some issues require proof on a balance of probabilities. Under sections 16(2) and (3), the party alleging exempting mental disorder must establish the disorder and its required incapacitating effect. Stone imposes an exceptional burden for automatism. Due diligence in strict liability and entrapment have their own burdens as well.

The persuasive burden under these rules must be kept separate from evidential screening. Fontaine clarifies the preliminary air-of-reality inquiry; it does not transfer every ultimate defence burden to the Crown. Likewise, failure to establish an exceptional defence does not automatically establish all the elements of the offence.

Use the following comparison to keep function, proof and outcome together. The linked lessons supply the complete conditions; the table does not replace them.

The balance-of-probabilities entries concern final persuasion. They do not authorize the screening judge to choose the more credible account before a supported defence reaches the trier of fact (fascicule 1, nos 37–39; fascicule 11, nos 28–30; fascicule 12, nos 9–21; fascicule 14, nos 92–93 and 108–109).

Judicial Screening

Air of reality

The air of reality inquiry asks whether there is evidence capable of supporting the defence's required elements so that a properly instructed trier of fact, acting reasonably, could accept it. The judge considers the evidence in the manner favourable to putting a supported defence before the trier of fact, without deciding witness credibility or resolving competing factual accounts.

Where the defence relies on circumstantial evidence, the judge may consider whether the necessary inferences are reasonably available. Speculation is insufficient. Screening is therefore not a mechanical acceptance of every assertion, but it must not become the final weighing of the defence.

For automatism, Fontaine explains the importance of an allegation of involuntariness supported by logically probative opinion from a qualified expert. Corroborating evidence is not an additional universal prerequisite at the screening stage. The final trier of fact may then evaluate the expert evidence and the other relevant circumstances.

Alternative defences and fair instructions

More than one defence may arise from the record, including alternatives based on different possible factual findings. Each must have its own foundation. A judge must leave a properly supported defence for consideration even if counsel has not used its correct label, while respecting the rules protecting the accused's control of a mental-disorder defence and trial fairness.

Inconsistent factual possibilities should not be combined into an invented account unsupported by the evidence. Nor should one defence's burden, objective standard or outcome be imported into another.

Worked Example

Factual Scenario

In this hypothetical, Léo is charged with assault arising from an encounter with Pat. Léo says he first pushed Pat to escape a tight grip on his arm. A witness confirms the grip and release. Pat then struck Léo's head; a later punch by Léo is also alleged. Léo recalls nothing after the head injury. A qualified expert with relevant neurological expertise examines the medical record and gives an opinion that Léo lost conscious control after the documented head injury and that the later movements occurred during that state. The Crown has contrary expert evidence and a witness who describes the later punch as purposeful.

Separate the alleged acts. Identify which defence has evidence supporting which conditions, and whether the judge should resolve the disagreement between experts at the screening stage.

Variation

The expert only confirms that people sometimes forget stressful events and expressly gives no opinion supporting involuntary movement. Léo offers no other evidence of loss of conscious control. Does the earlier screening result survive?

Practice Checklist

• Identify the charge, elements, fault standard and jurisdiction.
• State what the proposed argument would negate, justify, excuse or remedy.
• Find evidence supporting every required condition.
• Separate evidential screening from the ultimate persuasive burden.
• Apply the correct result: acquittal, lesser offence, special verdict or procedural remedy.
• Check each alternative defence independently and preserve the Crown's remaining burden.