As might have been anticipated, this review of the cases reveals that the circumstances of sexual offending, and of sexual offenders, are almost infinitely variable. That, in turn, means that the sentence imposed in one case can provide only very limited guidance in deciding what sentence should be imposed for a similar offence in another case. However, some conclusions can be drawn, as follows:
(1) An average starting point for a case of penile penetration of the vagina without consent, absent circumstances of aggravation, is in the order of 7 years' imprisonment under the former sentencing regime, or around 4 years and 8 months' imprisonment under the transitional regime. That starting point takes no account of any factors in mitigation.
(2) Because the circumstances of sexual offending and sexual offenders are so variable, nothing will be achieved by specifying a range of sentences customarily imposed. The range of potential aggravating features is so huge that features of that kind can either dramatically increase the sentence imposed (bearing in mind that the maximum sentence for an aggravated offence is 20 years' imprisonment: s 326 of the Criminal Code) or have little or no effect on the sentence imposed. The range of potential mitigating factors is at least equally extensive. They might result in a very large reduction in sentence or little or no reduction.
(3) Nor will anything be achieved by specifying a different starting point for each category of sexual penetration without consent. It should not be assumed that one form of sexual penetration is necessarily more, or less, serious than another. As Wheeler JA pointed out in C v The State of Western Australia [2006] WASCA 261 [35], there is no 'hierarchy of sexual penetration'. For example, although digital penetration will ordinarily be less serious than penile penetration, that is not inevitably so. It might, in particular circumstances, be no less serious or even more serious. The seriousness of every offence of unlawful sexual penetration must be determined by its own individual circumstances: C [35] (Wheeler JA); Cavill [266] - [267] (Miller JA).
That seems to me to be about as much guidance as can be obtained from the cases. I appreciate that it is less than sentencing judges might wish. However, that is a necessary consequence of the court's obligation to tailor each sentence to the individual circumstances of the case, having regard for the maximum penalty provided by the legislature and, to the extent that they can be of assistance, sentences customarily imposed in similar circumstances [68] - [69].