National rates
Over the 4-year period from 2008-09 to 2011-12, the rate of young people aged 10-17 under youth justice supervision in Australia on an average day remained at about 26-27 per 10,000. (Western Australia and the Northern Territory did not participate in the Juvenile Justice National Minimum Data Set during 2011-12. Where possible, estimates for these jurisdictions are included in the national totals. They are excluded from all state and territory comparisons.)
There was little change in the national rates of young people either under community-based supervision (about 22-23 per 10,000), or in detention (3.5-3.7 per 10,000).
States and territory rates
Despite this stability nationally, there were differences in trends among the states and territories for which data were available, with some rates increasing and others decreasing over the 4-year period.
Rates of young people aged 10-17 under supervision on an average day increased in Victoria (from 17 to 19 per 10,000 population) and the Australian Capital Territory (from 30 to 33 per 10,000).
Rates decreased markedly in South Australia (from 30 to 23 per 10,000) and Tasmania (from 47 to 40 per 10,000), and slightly in New South Wales (from 27 to 26 per 10,000) and Queensland (from 29 to 28 per 10,000).
Rates by Indigenous status and sex
Nationally, the level of Indigenous over-representation among young people under supervision increased slightly over the 4 years. In 2011-12, Indigenous young people were 16 times as likely as non-Indigenous young people to be under supervision on an average day in 2011-12, up from 15 times as likely in 2008-09.
This was mainly due to an increase in the rate of Indigenous young people aged 10-17 under supervision on an average day (from 226 to 236 per 10,000), while the rate for non-Indigenous young people remained stable.
Over the 4-year period the rate of young women aged 10-17 under supervision on an average day increased (from 8 to 10 per 10,000), while the rate for young men remained stable (about 42-43 per 10,000). In 2011-12 young men were 4 times as likely to be under supervision as young women, down from 5 times as likely in 2008-09.
Time under supervision
There was little change in the amount of time that young people spent under youth justice supervision during the year between 2008-09 and 2011-12 (178-185 days for each year). This was the case in both community-based supervision (175-181 days) and detention (62-63 days).