appeal against sentence — using carriage service to access child exploitation material offence contrary to s 474.19(1)(a)(i) of Commonwealth Criminal Code — state offence — original sentence imposed 2 years’ imprisonment with recognizance release order after 9 months for Commonwealth offence — guilty plea — s 16A(2)(g) — clear differentiation in sentencing judge’s treatment of guilty pleas to State and Commonwealth offences makes plain that did not take into account utilitarian value of guilty plea for Commonwealth offence — referred to plea being “entered in the face of a strong Crown case” — relevant to subjective factor of degree to which offender willingly facilitated course of justice rather than to objective utilitarian value of plea — applying law as then understood — utilitarian value of pleas to each offence identical — reflecting utilitarian value of plea to Commonwealth offence would allow 25 per cent — totality — sentencing judge indicated during the course of submissions that minded to make more than minimal but something less than complete accumulation — in result accumulation was complete with sentence for Commonwealth offence commencing upon expiration of non-parole period for State offence — no error in judge considering that further period of custody should be required in respect of State offence — error in judge saying intended partial accumulation but imposing total accumulation — objective seriousness — evidence as to which files accessed referred to immediately after stated assessment of objective seriousness of offences — could not prove which files offender had viewed — for example no evidence viewed any of Category 5 material, corollary no evidence not viewed material in that category — 100 files found on offender’s computer thus Commonwealth offence related to only 576 rather than whole 676 files — matters raised do not warrant criticism of sentencing judge’s assessment of objective seriousness of offences as below-midrange but not at bottom of range — appeal allowed — offender resentenced to 1 years’ and 10 months imprisonment with recognizance release order after 9 months