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7. Defences:Self-Defence General Available as a defence to all offences (unlike provocation). A self-help defence. Restriction of self-defence:
* Not available if death inflicted to protect property or trespass to property: s420
Differing values placed on property/the sanctity of life.
* Excessive self-defence: self-defence is a partial defence when the accused used excessive-force.
* A complete defence to criminal liability
* Reasonable response
Excessive self-defence: s421
* Partial defence: reduces conviction from murder to manslaughter
* Unreasonable response Elements of Self-defence 418 Self-defence-when available (1) A person is not criminally responsible for an offence if self-defence is established. (2) A person carries out conduct in self-defence if and only if the person believes the conduct is necessary: (a) to defend himself or herself or another person, or (b) to prevent or terminate the unlawful deprivation of his or her liberty or the liberty of another person, or (c) to protect property from unlawful taking, destruction, damage or interference, or (d) to prevent criminal trespass to any land or premises or to remove a person committing any such criminal trespass, and the conduct is a reasonable response in the circumstances as he or she perceives them.
1. The accused raises self-defence by establishing an evidentiary burden.
* To satisfy the evidentiary burden, the accused must show sufficient nexus between offence and threat
- there needs to be a relationship of (perceived) attack and a reasonable defence to it (proximity is relevant): Burgess; Saunders.
2. The prosecution must disprove, beyond all reasonable doubt, the possibility of self-defence: s 419. In order for self-defence to occur, the following requirements must be satisfied (s 418 (2)): A. Necessity of response - the accused believed that his conduct was necessary in order to: (a) defend oneself or another person or (b) stop/escape unlawful deprivation of liberty, or (c) protect property from being taken/damaged/interfered with, or (d) prevent criminal trespass or to remove a trespasser.
This is a subjective test, things like intoxication can be taken into account: Katarzynski 
Not limited to threats of death or GBH;
s 420: protection of property or prevention of trespass is valid for self-defence of assault but not homicide;
Threat do not need to be directed to the accused: s 418 (2)(a)
Conduct prompting defence can be lawful conduct: s 422
Must be a nexus between the offence and the threat: Burgess; Saunders 
Where the accused is the initial aggressor, question for the jury is whether the original aggression has ceased.
Battered women's syndrome: Runjanjic and Kontinnen (1991); 1
7. Defences:Self-Defence B. Reasonableness of response - the response of the accused was a reasonable response to the circumstances as the accused perceived them.
This is an objective test. However, not completely objective.
* "s418(2) is concerned not with the state of mind of a reasonable person but with the reasonableness of the conduct of the accused having regard to his or her state of mind": Crawford 
Intoxication is not relevant: Katarzynski ; s 428F (Intoxication in relation to the reasonable person test)
Reasonableness not an exact calculation (based on proportionality): Colon (1993)
Where the conduct is not a reasonable response but the accused believed the conduct was necessary, the accused may be criminally responsible for manslaughter instead of murder: s 421
3. If the prosecution cannot disprove the above elements beyond reasonable doubt, the actions done by the accused bear no criminal responsibility (complete defence): s 418 (1).
1. The accused has been indicted for murder and is currently standing trial before a jury.
2. The deceased was shot by the accused following a number of altercations between them in a hotel in Liverpool in the early hours of the morning of 6 April 2001.
3. There is ample evidence before the jury that the accused was intoxicated as a result of his voluntary consumption of alcohol at the time of the shooting.
4. There is no issue that the accused committed the act which caused the death of the deceased although, it will be a matter for the jury to determine whether the act causing death was voluntary and whether the accused at the time of firing the gun had the necessary mental state for the offence of murder.
How to assess objectively based on personal characteristics.
1. The appellants had been convicted of malicious damage of property after painting the words "No War" on one of the sails of the Sydney Opera House and submitted that they were entitled to have the jury consider self-defence.
2. The trial judge barred self-defence from being considered. Issue: Can the trial judge prevent self-defence from being considered?
Held, Appeal dismissed.The accused's self-defence was not permitted to go to the jury.
Katazynski  NSWSC 613
* The question now posed for the jury, where there is evidence raising self-defence, is not the same as it was at common law after Zecevic v DPP and as it was considered in Conlon.The questions to be asked by the jury under s 418 are:
* is there is a reasonable possibility that the accused believed that his or her conduct was necessary in order to defend himself or herself; and,
if there is, is there also a reasonable possibility that what the accused did was a reasonable response to the circumstances as he or she perceived them.
* The first issue is determined from a completely subjective point of view considering all the personal characteristics of the accused at the time he or she carried out the conduct. The second issue is determined by an entirely objective assessment of the proportionality of the accused's response to the situation the accused subjectively believed he or she faced.
The Crown will negative self-defence if it proves beyond reasonable doubt either (i) that the accused did not genuinely believe that it was necessary to act as he or she did in his or her own defence or (ii)that what the accused did was not a reasonable response to the danger, as he or she perceived it to be.
* The issue as to the reasonableness of the accused's response is objective in so far as the jury is not concerned with what the accused believed was necessary to respond to the circumstances as he or she perceived them to be. The current provision is not concerned with whether the accused's belief as to what was the necessary response was a reasonable one or whether he or she had reasonable grounds for that belief. This is where the current provisions are in contrast to the position at common law: the accused need not have reasonable grounds for his or her belief that it was necessary to act in the way he or she did in order to defend himself or herself. It is sufficient if the accused genuinely holds that belief.
* It will be a matter for the jury to decide what matters it should take into account when determining whether the response of the accused was reasonable in the circumstances in which he or she found himself or herself. The jury is not assessing the response of the ordinary or reasonable person but the response of the accused. In making that assessment it is obvious than some of the personal attributes of the accused will be relevant just as will be some of the surrounding physical circumstances in which the accused acted. So matters such as the age of the accused, his or her gender, or the state of his or her health may be regarded by the jury. Whether or not some particular personal characteristic of the accused is to be considered will depend largely upon the particular facts of the case.
* But in my opinion one matter that must be irrelevant to an assessment of the reasonableness of the accused's response is his or her state of sobriety. As was pointed out in McCullough, it is logically incongruous "to contemplate the proposition that a person's exercise of judgment might be unreasonable if he was sober, but reasonable because he was drunk". Apart from Conlon, I am not aware of any other decision that has held that intoxication is a matter relevant to an evaluation of the reasonableness of the conduct or belief of a person. It is not relevant at common law to an evaluation of the accused's response to provocation or the belief of a reasonable person as to the dangerousness of the accused's actions for the offence of manslaughter. Burgess; Saunders  NSWCCA 52
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