15 In the context of the above well established sentencing principles it will also be necessary to have regard to those general matters going to aggravation, mitigation and other factors identified in s 21A (1) of the CSPA relevant to the defendant. As was said in R v Way at [56]:
... it is not to be overlooked that there is a well established body of principles that have been developed by the courts over a long period of time. By providing guidance in the form of a list of aggravating and mitigating factors in s 21A, the Parliament did not intend to overrule or disturb those principles or restrict their application. In so far as those principles refer to factors, whether objective or subjective, that affect the 'relative seriousness' of the offence, they are expressly preserved by s 21A(1)(c).
16 Ultimately, all of the above factors must be considered as part of 'a complex of inter-related considerations' (See R v Gallagher (1991) 23 NSWLR 220). Having said that, as was said by Spigelman CJ in Thorneloe v Filipowski (2001) 52 NSWLR 60 at 69, it still remains for the sentencing judge to ensure:
... that a sentence should be proportionate to the objective gravity of the offence. This necessarily requires a sentencing judge to consider, at some stage in the reasoning process, the sentence that is appropriate for the particular circumstances of the crime without reference to the subjective case of the particular offender.
17 In Markarian v The Queen [2005] HCA 25: 18 May 2005, the High Court, by majority (Kirby J dissenting) generally disavowed the sequential or two tiered approach to sentencing. In doing so, their Honours did not entirely reject the proposition that, in some circumstances, 'an arithmetical process' would be appropriate. As they said at [39]:
Following the decision of this Court in Wong it cannot now be doubted that sentencing courts may not add and subtract item by item from some apparently subliminally derived figure, passages of time in order to fix the time which an offender must serve in prison. That is not to say that in a simple case, ... indulgence in arithmetical deduction by the sentencing judges should be absolutely forbidden. ... The law strongly favours transparency. Accessible reasoning is necessary in the interests of victims, of the parties, appeal courts, and the public. There may be occasions when some indulgence in an arithmetical process will better serve these ends . ... (emphasis added)
18 On that point, McHugh J also acknowledged the need, where appropriate, for the awarding of a nominated discount for 'some factor'. As he said at [74]:
...The distinction between permissible and impermissible quantification of "discounts" on a sentence will usually be found in whether the quantification relates to a sentencing purpose rather than some other purpose. So, the quantification of the discount commonly applied for an early plea of guilty or assistance to authorities is offered as an incentive for specific outcomes in the administration of criminal justice and is not related to sentencing purposes. The non-sentencing purpose of the discount for an early guilty plea or assistance is demonstrated by the fact that offenders are ordinarily entitled to additional mitigation for any remorse or contrition demonstrated with the plea or assistance, aside from the discount for willingness to facilitate the course of justice...