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Module 7 · Defences

Self-defence is examined every year from 2022 to 2025, in both directions, succeeding and failing. Duress appears in 2023 and 2025, emergency in 2021, and intoxication threads through everything to 2024. The examined skills are defence selection and a clean statement of the onus. Every defence is a twist on the offence: the offence stands unless the defence untwists it, and s 322I fixes who must untwist and to what standard.

The three defences are confused with each other more than any other doctrines in the subject, because all three respond to pressure. Hold three signatures. Self defence blocks or wards off an unjust threat with defensive force against the attacker. Duress answers a human demand backed by a threat of harm by committing the demanded offence. Emergency answers a peril arising from circumstances rather than from a demand, usually by harming an innocent person or their property.

Cases at a glance

Selection and onus

Really serious injury in these murder thresholds includes serious sexual assault (s 322H), so a threatened serious sexual assault opens all three defences on a murder charge.

The three signatures on the facts

Ask first at whom the conduct was directed and why. Defensive force lands on the attacker, and that is self defence. Duress conduct is a separate offence committed because a person demanded it under threat, and it lands on someone other than the threatener. Emergency conduct answers a circumstance such as fire, flood or a runaway vehicle, and it typically falls on an innocent person or property because there is no attacker to resist. The demand is the tell for duress. Danger without a demand or an attacker is emergency. Meeting an attacker with force is self defence even if the moment also felt like an emergency. Selection is a gate, and if the structure points to self defence, running emergency earns nothing however well its elements are argued.

Onus discipline

State the onus in the same words every time. The accused carries only the evidential burden to raise the defence on the evidence, and the prosecution must then disprove it beyond reasonable doubt (s 322I). The evidential burden is not a burden of proof. The accused proves nothing and merely points to evidence capable of raising the defence, which may come from the prosecution case itself. Disproof of any one element or limb beyond reasonable doubt defeats the defence, so identify the limb the prosecution will attack. Writing that the accused must prove self defence on the balance of probabilities inverts s 322I. The one true exception is mental impairment, which the accused proves (M8).

Self-defence

• The scope is wider than defence of the person. The note to s 322K includes defence of the accused or another person, preventing or stopping the unlawful deprivation of the liberty of the accused or another person, and protection of property. For murder the defence remains available only where the accused believed the threat was of death or really serious injury (s 322K(3)), so force used to protect property alone cannot answer a murder charge.
• Proportionality is no longer a separate requirement, and failure to retreat is not a bar. Both are factors in the two limbs (Zecevic).
• Family violence: where self-defence is in issue, evidence of family violence may bear on both the belief and the reasonableness, even where the harm was not immediate or the response exceeded the harm threatened (s 322M). Section 322J(1) lists the admissible categories of that evidence. Family violence is not a separate defence and is argued inside the elements of self-defence.

Limb one, the belief in necessity

The first limb is subjective. A genuine belief that the conduct was necessary satisfies it even if the belief was mistaken or formed while intoxicated (Zecevic). An accused grabbed from behind in the dark who strikes a person who was in fact harmless can still satisfy the limb, because it asks what the accused believed rather than what was true. The limb is fought by testing the belief against the specific acts done rather than the decision to act. Believing that some intervention was necessary is not the same as believing that this blow or the third stamp was necessary.

Limb two, the reasonable response

The second limb is objective but judged on the circumstances as the accused perceived them (Katarzynski). Stand in the accused's shoes and ask whether the response was reasonable, without judging it too finely (Zecevic). Proportionality is no longer a separate requirement and failure to retreat is not a bar. Both are factors inside the limbs (Zecevic). The usual battleground is continuation. Force that was reasonable while the threat was live becomes unreasonable once the attacker is down, and no view of the perceived circumstances rescues further violence against a motionless person.

Aggressors and known lawful conduct

Being the original aggressor is not an automatic bar, since an original aggressor may still rely on self defence (Zecevic). Nor does starting the fight license everything that follows. Continuing aggression makes the belief and the reasonableness hard to sustain, so the argument runs inside the two limbs rather than as a threshold rule. The cleanest frame is two separate attacks. Ask whether the accused's original aggression had ceased before the response now being judged, looking for something that ended it, such as declining further conflict or quitting the use of force. If the aggression had ceased and the other side began a fresh attack, the defence runs on ordinary terms. If it had not, the accused is acting as an aggressor in pursuit of the original design rather than in self defence (Zecevic). Section 322L is a true threshold. Self defence does not apply to a response to conduct the accused knew was lawful, such as a lawful arrest (s 322L). Knowledge is the key word. An accused who did not know the conduct was lawful, as where a plain clothes officer grabs them without a word, is outside s 322L.

Duress and emergency

• Murder needs a threat of death or really serious injury (s 322O(4)), and there is no duress where the accused voluntarily associated with the threatener for the purpose of violent conduct (s 322O(3)). Reasonableness takes account of the accused's characteristics, such as sex, maturity and family violence (DPP v Parker; s 322P), but not self-induced intoxication (s 322T).

The duress checklist walked

Duress has three working parts and each can be fought. First, a reasonable belief that a threat of harm has been made that will be carried out unless an offence is committed (s 322O). That standard is stricter than the genuine belief that opens self defence, so an honest but unreasonable fear does not carry it. Three refinements sharpen the element. The threat may be directed at any person rather than at the accused, and in DPP v Parker the threats were against the accused's family. The element is the belief, so a reasonable belief that a threat has been made suffices even if no threat was actually made (s 322O(2)(a)). And the belief is that the threat will be carried out unless an offence is committed, so the compelled conduct need only be an offence rather than the specific offence charged. Second, committing the offence must have been the only reasonable way to avoid the harm, so an available alternative such as seeking help defeats the element unless it was not a reasonable course on the facts. Test the alternative against the threat rather than in the abstract. An available escape or a report to police defeats the element only where it would actually nullify the threat, and in family violence contexts a continuing threat can survive both, which is one reason evidence of family violence is made relevant to duress (s 322P). Third, the conduct must have been a reasonable response to the threat. The threat need not be fresh or spoken, because continuing and implicit threats can found duress (Rowan). A standing threat that the accused's family will suffer if they ever refuse remains live when the demand comes weeks later with nothing new said. The reasonable belief standard has a set formulation. Ask whether a reasonable person possessing the personal characteristics of the accused that might have affected the accused's appreciation of the circumstances might have held the belief (DPP v Parker). That is how sex, maturity and family violence enter the standard (s 322P), and self induced intoxication never does (s 322T).

The emergency checklist walked

Emergency mirrors duress with a circumstance in place of a threatener, and its usual battleground is the only reasonable way element (s 322R). A genuine emergency does not excuse whatever response followed. Where an accused speeding a sick child to hospital passed open hospitals and waved away an offer to call an ambulance, reasonable alternatives existed and the element fails even though the emergency was real. The reasonable belief standard carries the same formulation as duress. Ask whether a reasonable person possessing the personal characteristics of the accused that might have affected the accused's appreciation of the circumstances might have held the belief (DPP v Parker).

The three defences compared

The murder thresholds and the s 322I onus are common ground and sit in the selection table above.

Intoxication

Routing the intoxication

Intoxication is a modifier rather than a defence, and the whole skill is routing it. If it is said to show that the accused did not act voluntarily or did not form the intention, the route is the common law in O'Connor and the analysis belongs inside the offence elements under the prosecution's ordinary burden. If it is said to explain a mistake or a reaction inside self defence, duress or emergency, the route is s 322T. Section 322T has no work to do where no defence is raised, and O'Connor has no work to do on the reasonableness limbs. Calibrate the O'Connor route honestly. Modest drinking rarely raises a real doubt that intent was formed, and a drunken intent is still an intent (O'Connor). Flagging the need for real evidence of impairment is itself good exam craft.

When intoxication is not self induced

Section 322T(5) gives the full list. Intoxication is not self induced where it came about involuntarily, or because of fraud, sudden or extraordinary emergency, accident, reasonable mistake, duress or force, or from a prescription drug used in accordance with the directions of the person who prescribed it, or from a legal non prescription drug used for a purpose, and at the dosage level, recommended by the manufacturer (s 322T(5)). Where the intoxication is not self induced, the standard changes rather than disappears. Regard must be had to the standard of a reasonable person intoxicated to the same extent as the accused (s 322T(4)), so the reasonable person is placed in the same blameless fog the accused was in. One rule then closes the compliant use routes. Even prescription compliant or dosage compliant use is self induced where the person knew, or had reason to believe, that the drug would significantly impair their judgment or control (s 322T(6)). The carve out is narrow. Taking triple the prescribed dose to get high is not compliant use, so the intoxication is self induced and excluded whatever the label on the bottle said.

How the examiners mark it

Defences are step four of the problem method. They come after a prima facie offence is established, so never open an answer with a defence. When a defence arises, the burden sentence comes first. Note the evidential burden and how it is discharged on the facts, then say who must disprove the defence and to what standard. That one disciplined sentence separates answers at a glance.

Triage the limbs the way you triage elements. Where a limb is obviously satisfied, say so briefly with the fact that shows it, and spend the length on the limb that is genuinely contested. Kill a doomed defence in a line or two rather than omitting it. Conclude in likelihood language rather than verdicts. The prosecution could not disprove the belief limb beyond reasonable doubt. A jury might be reluctant to find the response unreasonable. That calibrated register is rewarded on its own, separately from issue coverage. The predictable losses are selecting the wrong defence, inverting the onus, and arguing the belief limb without testing the specific acts.

Critical pitfalls and counter-arguments

Counter-arguments both ways

Each defence has a standard prosecution attack and a standard defence answer, and the marks sit in running both before concluding.

• Disproportion. The prosecution says the response went far beyond the threat. The defence answers that the response is not judged too finely and is measured on the circumstances as perceived (Zecevic; Katarzynski). Resolve it on timing, because force after the threat has ended is where the objective limb genuinely fails.
• The stale threat. The prosecution says nothing was threatened on the day. The defence answers that continuing and implicit threats can found duress (Rowan). Resolve it on whether the standing threat was still live between the parties.
• The original aggressor. The prosecution says the accused started it. The defence answers that an original aggressor may still rely on self defence (Zecevic). Resolve it inside the limbs, since continuing aggression makes belief and reasonableness hard to sustain.
• The prescription pills. The defence says the drugs were prescribed so the intoxication was not self induced. The prosecution answers that the carve out covers only use in accordance with the prescription or the relevant dosage level, so exceeding the dose returns the intoxication to the self induced rule (s 322T).

Take it to the practice bank

This module is drilled in the Criminal Law practice bank. Every problem there carries a realistic Pass answer, an H1 model answer, and an examiner's comment explaining the decisive fact and where the marks are lost.

Practice prompts

1. Select the defence by structure on a set of facts, and say why the attractive wrong one does not fit.
2. Write the onus sentence once, and use exactly the same words every time you raise a defence.
3. Argue both limbs of self defence, and test the belief against the specific act the accused did.
4. Take an intoxicated accused and route the intoxication correctly, to the defence or to the fault element.
5. Explain how evidence of family violence works inside self defence rather than as a defence of its own.