Self Defence

The law permits a full defence to a charge laid if the Crown are unable to negative self-defence.

The law of self-defence is as set out at sections 418 to 423 of the Crimes Act 1900. In short, a person acts in self defence 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.

Section 419 makes it very clear that it is for the Crown to negative self defence once it is raised by the evidence.

The cases below hold that the Crown bears that onus even where self defence is not explicitly relied by the Defendant (Mencarious v R [2008] NSWCCA 237).


R v Katarzynski [2002] NSWSC 924

“The questions to be asked by the jury under s 418 are: (i) 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, (2) 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.”