The rate of young people under youth justice supervision varies among the states and territories. In part, this reflects differences in legislation, policy and practice.
On an average day in 2011-12, the rate of young people aged 10-17 under supervision on an average day in 2011-12 was lowest in Victoria at 19 per 10,000, and highest in Tasmania, at 40 per 10,000. (Western Australia and the Northern Territory did not participate in the Juvenile Justice National Minimum Data Set during 2011-12 and are excluded from all state and territory comparisons.)
Although young people in all states and territories were more likely to be under community-based supervision than detention, rates varied across jurisdictions.
There were also differences in the age profiles of young people under supervision. Most of those under supervision in each state and territory on an average day during 2011-12 were aged 14-17, although the proportions varied (64-88%). Only 2-8% were aged 10-13, while 6-32% were aged 18 and older.
In most jurisdictions, young people aged 10-17 who commit an offence are processed in the youth system. However, in Queensland, young people aged 17 or over at the time that they allegedly commit offences are processed in the adult criminal justice system, which results in a younger population under youth justice supervision (on average). In Victoria, some young people aged 18-20 may be sentenced to detention in a youth facility (known as the 'dual track' system) which results in an older population, on average. See also Age range for treatment as a young person.
The total amount of time young people spent under supervision varied between states and territories. When all supervision periods during 2011-12 are considered, those in South Australia spent the least amount of time under supervision (22 weeks or 152 days on average) and those in Queensland spent the most (30 weeks or 208 days).