State and territory trends

Key findings

On an average night in the June quarter 2024:

  • the number of young people aged 10 and over in detention was lowest in the Australian Capital Territory (16) and highest in Queensland (317)
  • the rate of young people aged 10–17 was highest in the Northern Territory (22 per 10,000) and lowest in Victoria (0.7 per 10,000). 

On an average night from the June quarter 2020 to the June quarter 2024:

  • the Northern Territory consistently had the highest rate of young people aged 10–17 in detention (6.6–22 per 10,000)
  • the rate of young people in detention increased in New South Wales, Queensland, Tasmania and the Northern Territory, and declined in Victoria and Western Australia. South Australia and the Australian Capital Territory remained largely steady. 

Overview

The size of youth justice populations in states and territories can be affected by the population size of that state or territory, as well as by differences in state legislation, policies and practices, including the available types of supervised orders and options for diversion. For more information see Youth Justice in Australia 2022–23 – appendices B to D.

In 2023, the Northern Territory and the Australian Capital Territory raised the minimum age of criminal responsibility to 12 (from 10). This means that young people aged 10 and 11 cannot be held criminally responsible for their conduct and cannot be supervised in the youth justice system during 2023–24. For more information see Raising the age of criminal responsibility.

The rates for the Australian Capital Territory and Northern Territory are for young people aged 10–17 between June quarter 2020 and June quarter 2023, and for young people aged 12–17 during 2023–24.

For ease of interpretation, this report will refer to rates for young people aged 10–17, even when the rates are for the 12–17 population (Australian Capital Territory and Northern Territory in 2023–24). For more information see Technical notes – Rates.

The number of young people in detention by state and territory

On an average night in the June quarter 2024:

  • Queensland had the highest number of young people in detention (317), followed by New South Wales (240) and Victoria (88)
  • the Northern Territory had the highest rate of young people aged 10–17 in detention (22 per 10,000), followed by Queensland (5.1 per 10,000)
  • the Australian Capital Territory had the lowest number of young people aged 10 and over in detention (16), followed by Tasmania (21) and South Australia (36)
  • Victoria had the lowest rate of young people aged 10–17 in detention (0.7 per 10,000), followed by South Australia (1.8 per 10,000) (Figure 4.1).

Figure 4.1: Young people in detention on an average night, by state and territory, June quarter 2020 to June quarter 2024 (number and rate)

Over the 4-year period, the number of young people in detention increased in all jurisdictions except Victoria , Western Australia and the ACT.

Over the 4-year period, the number of young people in detention increased in all jurisdictions except Victoria , Western Australia and the ACT.

Notes

  1. Rates are for young people aged 10–17. Numbers include young people aged 10 or over who are under youth justice supervision. For numbers of young people aged 10–17 only, refer to the supplementary tables on Data.
  2. Rates are the number of young people per 10,000 relevant population.
  3. Rates are not published where there were fewer than 5 young people.
  4. Trends among small populations should be interpreted with caution. Numbers tend to fluctuate from quarter to quarter due to random variation, and this might affect the appearance and interpretation of trends.
  5. Rates are calculated from the unrounded average nightly populations and are not published when there are fewer than 5 young people in the numerator. There might be instances when a numerator is presented as 5 due to rounding, and the rate is not calculated (see Technical notes).
  6. Numbers might not add up to the total due to rounding.
  7. In August 2023, the Northern Territory raised the minimum age of criminal responsibility from 10 to 12. The rates for the Northern Territory in 2023–24 are for young people aged 12–17.
  8. In November 2023, the Australian Capital Territory raised the minimum age of criminal responsibility from 10 to 12. The rates for the Australian Capital Territory in 2023-24 are for young people aged 12–17.

Source: Supplementary tables S11, S18, S29, S36, S47 and S54.

Changes in the rate of young people in detention over the 4-year period in each state and territory

On an average night over the 4-year period from the June quarter 2020 to the June quarter 2024:

  • overall, the Northern Territory had the highest rate of young people aged 10–17 in detention on an average night each quarter (6.6–22 per 10,000). The rate peaked in the September quarter 2023 after being at its lowest in the June quarter 2020. This rate increase is consistent with increases in the number of young people in detention (numerator) and decreases in the total in-scope population (denominator), as per the increased age of criminal responsibility in the Northern Territory from 10 to 12 years old in 2023–24. These rates are not comparable with those prior to 2023-24 for the Northern Territory, which include all young people aged 10–17 in the denominator
  • the rate of young people in detention increased in Queensland, New South Wales, Tasmania and the Northern Territory and declined in Victoria and Western Australia. Rates in South Australia fluctuated over this period and did not follow a clear trend
  • the states with the highest number of young people aged 10 and over in detention were Queensland (200–334), followed by New South Wales (170–240), Victoria (88–180) and Western Australia (82–127)
  • since the September quarter 2020, Queensland has had the highest number of young people in detention on an average night
  • the size of the youth detention population fell in Victoria and Western Australia (Figure 4.2)
  • trends in detention could not be reliably determined in the Australian Capital Territory due to small numbers.

State and territory differences by legal status

Northern Territory detention data for legal status were unavailable between September quarter 2023 and June quarter 2024. Therefore, the Northern Territory is excluded from this section. 

On an average night in the June quarter 2024, the rate of young people aged 10–17:

  • in unsentenced detention ranged from 0.5 per 10,000 in Victoria to 4.4 per 10,000 in Queensland
  • in sentenced detention ranged from 0.2 per 10,000 in Victoria to 1.3 per 10,000 in Western Australia (among the states and territories for which data is available) (Figure 4.2).

Over the 4-year period (from June quarter 2020 to June quarter 2024), the rate of young people aged 10–17 in unsentenced detention:

  • increased in Queensland from a low of 3.0 per 10,000 in the September quarter 2020 to 4.9 per 10,000 in the March quarter 2023
  • declined in Victoria from a high of 1.5 per 10,000 in the June quarter 2020 to 0.5 per 10,000 in the June quarter 2024.

Trends in unsentenced detention could not be reliably determined in Tasmania and the Australian Capital Territory due to small numbers. 

Over the same 4-year period, the rate of young people aged 10–17 in sentenced detention fell overall in New South Wales (0.7 to 0.4 per 10,000), Victoria (0.4 to 0.2 per 10,000) and Western Australia (1.5 to 1.3 per 10,000).

Trends in sentenced detention could not be reliably determined in South Australia, Tasmania and the Australian Capital Territory due to small numbers (Figure 4.2).

Figure 4.2: Young people in detention on an average night, by legal status, by state and territory, June quarter 2020 to June quarter 2024 (number and rate)

The number and rate of young people in unsentenced detention was higher than sentenced detention across jurisdictions for most of the 4-year period.

The number and rate of young people in unsentenced detention was higher than sentenced detention across jurisdictions for most of the 4-year period.

Notes

  1. Numbers might not add up to the total due to rounding.
  2. Rates are for young people aged 10–17. Numbers include young people aged 10 and over who are under youth justice supervision. For numbers of young people aged 10–17 only, refer to the supplementary tables on Data.
  3. Rates are the number of young people per 10,000 relevant population.
  4. Rates are not published where there were fewer than 5 young people.
  5. Trends among small populations should be interpreted with caution. Numbers tend to fluctuate from quarter to quarter due to random variation, and this might affect the appearance and interpretation of trends.
  6. Rates are calculated from the unrounded average nightly populations, and are not published when there are fewer than 5 young people in the numerator. There might be instances where a numerator is presented as 5 due to rounding, and the rate is not calculated (see Technical notes).
  7. Rates for some quarters for Victoria, South Australia, Tasmania and the Australian Capital Territory are suppressed due to small numbers.
  8. In August 2023, the Northern Territory raised the minimum age of criminal responsibility from 10 to 12. The rates for the Northern Territory in 2023–24 are for young people aged 12–17.
  9. In November 2023, the Australian Capital Territory raised the minimum age of criminal responsibility from 10 to 12. The rates for the Australian Capital Territory in 2023–24 are for young people aged 12–17.

Source: Supplementary tables S29, S36, S47 and S54.