Several observations may be made in relation to the determination of the non-parole period where an offender is to be sentenced to life imprisonment for the new offence of murder and the sentencing court has decided to proceed under s 90(1)(a) of the Sentencing Act 1995 (WA) and fix a minimum period (instead of proceeding under s 90(1)(b) and ordering that the offender must never be released).
First, the considerations which the sentencing court must take into account in setting the non-parole period are all relevant sentencing factors, including the circumstances of the offence, all aggravating and mitigating factors and the offender's personal antecedents.
Secondly, the non-parole period must be set by reference to achieving or satisfying all relevant sentencing objectives, including punishment, retribution, personal deterrence and general deterrence.
Thirdly, sentencing dispositions under the previous legislative scheme will generally be of some assistance in determining the length of the non-parole period for the new offence of murder where the sentencing court has decided to impose life imprisonment and set a minimum period under s 90(1)(a) of the Sentencing Act. It is essential, however, to bear in mind the following:
(a) The increase in the statutory minimum period from 7 to 10 years was made in the context of eliminating from the definition of murder, the unlawful killing of another person where the offender (merely) intends to cause bodily injury of such a nature as to cause, or be likely to cause, permanent injury to the health of the person killed or another person.
(b) The strict ranges of available non-parole periods based on the distinctions under the previous legislative scheme between wilful murder and murder, and between wilful murder carrying strict security life imprisonment and wilful murder carrying (merely) life imprisonment, have been abolished. These strict ranges were not always appropriate to the facts and circumstances of a particular offender and his or her offending. The proper exercise of the sentencing discretion is no longer constrained by the rigidity of the previous legislative scheme (including the sentencing framework).
(c) The comments of Wheeler JA (McLure P & Owen JA agreeing) in Atherden [30] - [31].
Fourthly, the offender's intention in relation to the particular killing is a relevant fact or circumstance (invariably, if not always, a very significant matter) to be considered together with all the other relevant facts and circumstances of the offending and the offender in determining the appropriate non-parole period.
Fifthly, the removal of the demarcation between wilful murder and murder, and the abolition of the strict ranges of available non-parole periods under the previous legislative scheme, may result in some increase in the non-parole period for offending that would formerly have attracted a non-parole period at or very close to the upper limit of a previously applicable range [41] - [46].