When a court is sentencing an offender to imprisonment, it must first stipulate the non- parole period. Under s44 of the Crimes (Sentencing Procedure) Act 1999, the balance of time in that imprisonment must not exceed one-third of the non-parole period. This is unless there are special circumstances that the Court records for the case.
Special circumstances are found in a large majority of cases; most commonly in cases of young offenders (18-20 years old) and for the oldest offenders (70+ years old). It has been interpreted very widely in the case of Moffitt (1990) 20 NSWLR 114.. Special circumstances may include:
- Accumulation as per the case of Simpson (1992) 61 A Crim R 58
- Accumulation of subsequent sentences as per the case of Close (1993) 65 A Crim R 55.
- Young people with good prospects of rehabilitation, as per (Moffitt (1990) 20 NSWLR 114 at 121.
- Illness or disability, per the case of Sellen (1991) 57 A Crim R 313AIDS: Dwyer (1994) PD .
- Psychiatric illness, per the case of B (1993) 68 A Crim R 547
- Rehabilitation, per the case of Russell (1993) PD 
- Protection, per the case of Astill (No. 2) (1992) 64 A Crim R 289.
- Assistance and early plea, per the case of McLear (CCA 1/9/92)
- Broken periods of pre-sentence custody, per the case of Close as mentioned in point 2.
- Double jeopardy in a Crown appeal, per the case of McDonald (1998) 5 Crim LN