People in contact with the criminal justice system

The criminal justice system comprises 3 parts, the police (investigative element), courts (adjudicative element) and correctional services (corrective element). Information on alcohol and other drug use from each section of the criminal justice system is presented below.

Key findings

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Illicit drug offences (74,443 offenders) and acts intended to cause injury (78,523 offenders) were the most common principal offences nationally in 2019–20. The number of illicit drug offenders decreased by 4% (2,765 offenders) between 2018–19 and 2019–20 (ABS 2021b). Over two-thirds (68%) of illicit drug offenders were charged with the principal offence of 'possess and/or use illicit drugs' (ABS 2021b).


Data from Criminal Courts, Australia for 2019–20 showed that, excluding organisations and transfers to other court levels, most defendants had their offences finalised in the Magistrates’ Courts (91%, or 427,815 defendants).

  • Illicit drug offences were the 3rd most common principal offence among defendants finalised in the Magistrates’ Courts, accounting for around 1 in 10 (11%, or 44,993) defendants. Of these:
    • Over two-thirds (67%, or 30,301 defendants) were possession or use offences.
    • Almost three-quarters (74%, or 33,513) of defendants were male.
  • Excluding transfers, illicit drug offences steadily increased between 2010–11 (32,868 defendants) and 2016–17 (54,484), then declined in 2019–20 (44,993).
  • From 2018–19 to 2019–20, illicit drug offences decreased by 11% (6,812 defendants). Some of the decrease may be the result of ‘lower level’ offences (such as minor drug possession) being diverted from the courts (ABS 2021a).
  • Of defendants proven guilty in the Magistrates’ Courts for a principal offence of illicit drug offences (42,181 defendants), 3 in 5 (62%, or 25,960) were sentenced to fines. A further 7.9% were given a custodial sentence (ABS 2021a) (Table S3.55).

The introduction of COVID-19 restrictions in March 2020 led to the deferral of some cases and temporary court closures nationwide, which affected the number of defendants finalised in Criminal Courts. This should be taken into account when comparing the 2019–20 reference period with earlier years.

Corrective services

A snapshot of the adult (aged 18 and over) prison population at 30 June 2020 showed that there were 41,060 prisoners in Australia. This represents 202 prisoners per 100,000 adult population and is a 7% decrease from 2019 (ABS 2020).

Young people under youth justice supervision

On an average day in 2019–20, 5,323 young people aged 10 and over were under youth justice supervision. A total of 10,222 young people were supervised at some time during the year, down from 11,056 in 2015–16 (AIHW 2021b). On an average day in 2019–20, most young people under supervision (4,490, or 84%) were supervised in the community. However, around 1 in 6 (863, or 16%) were in detention and some were supervised in both the community and detention on the same day. In 2019–20, data collection included a period (March–June 2020) after COVID-19 restrictions were introduced in Australia. Data may not be comparable to previous years (AIHW 2021b).

From 1 July 2012 to 30 June 2016, young people aged 10–17 under youth justice supervision were 30 times as likely as the Australian population of the same age to receive alcohol and other drug (AOD) treatment from publicly funded AOD treatment services (AIHW 2018).

Tobacco smoking

The National Tobacco Strategy 2012–2018 recognises that prisoners have some of the highest levels of smoking and that smoking is common among groups that are often over-represented in the prison population (IGCD 2012). Recently, there have been a range of smoking bans introduced in Australian prisons and most correctional facilities are now smoke-free (DoH 2016).

Data from the National Prisoner Health Data Collection (NPHDC) showed that rates of smoking among prisoners is substantially higher than in the general community. In 2018:

  • Three-quarters (75%) of prison entrants currently smoked tobacco.
  • Tasmania had the highest proportion of current smokers (90%), followed by South Australia (83%). Queensland (68%) had the lowest proportion.
  • More than two-thirds (67%) of prison entrants smoked tobacco daily (Figure CRIM1).
  • The average age a prisoner smoked their first full cigarette was 14.1 years (AIHW 2019).

In the general population, findings from the 2019 National Drug Strategy Household Survey (NDSHS) showed that of people aged 14 and over:

  • 11.0% smoked on a daily basis.
  • 14.0% were current smokers.
  • The average age of their first full cigarette was 16.6 years (AIHW 2020).

Figure CRIM1: Smoking status for prison entrants and the general population, 2018 and 2019 (per cent)

The figure shows that 75% of prison entrants reported being a current smoker in 2018, and 67% reported being a daily smoker. These are higher proportions than for the general population, where 14.0% of people were current smokers and 11.0% were daily smokers in 2019. Conversely, prison entrants were less likely than the general population to be ex-smokers (10.0% compared with 22.8%) or never smokers (13.0% compared with 63.1%).

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Alcohol consumption

The risky consumption of alcohol has been found to be strongly associated with adverse outcomes including criminal offending (Fergusson, Boden & Horwood 2013).

The Drug Use Monitoring in Australia (DUMA) program is an ongoing monitoring program that captures information on illicit drug use among police detainees. Data from the 2020 DUMA indicate that alcohol consumption is common among police detainees.

  • Over 1 in 4 (28%) police detainees reported consuming alcohol in the 24 hours prior to their arrest, with a median of 11 standard drinks consumed prior to arrest.
  • Almost 1 in 6 (16%) police detainees reported that alcohol contributed to their most recent arrest, the same as in 2019. Among those who reported drinking in the 30 days before interview, this proportion was 29% (Voce & Sullivan 2021).

Prison entrants in 2018 were more likely than the general population to be non-drinkers, however those that did drink were more likely to drink at high risk levels than people in the general community (refer to Box CRIM1 for information on how alcohol related harm is calculated for prison entrants). Specifically:

  • Prison entrants aged 25–44 years were twice as likely to consume alcohol in greater quantities that those the same age in the general community (e.g. 7 or more standard drinks on a usual day of drinking) (AIHW 2019).
  • During the 12 months prior to prison, 34% of prison entrants consumed alcohol at levels that placed them at high risk of alcohol-related harm (AIHW 2019).

Prison entrants in the Northern Territory (60%) and Tasmania (40%) were the most likely to be at high-risk of alcohol-related harm, while those in South Australia (58%) and Queensland (35%) were the most likely to report that they do not drink (AIHW 2019) (Table S3.57).

Box CRIM1: Calculating alcohol-related harm for prison entrants

The proportion of prison entrants who are at risk of alcohol-related harm as determined using questions on alcohol consumption from the WHO’s Alcohol Use Disorder Identification Test (AUDIT) screening instrument. The AUDIT tool alcohol harm risk profile does not align with the alcohol risk guidelines and as such the results are not comparable to the general population (AIHW 2019).

Illicit drugs

It is commonly understood that there is a link between the use of illicit drugs and involvement in the criminal justice system. Illicit drug use has been identified as a primary motivating factor in non-violent property offences such as burglary and theft (Kopak & Hoffman 2014).

The Australian Criminal Intelligence Commission (ACIC) collects national illicit drug arrest data annually from federal, state and territory police services to inform the Illicit Drug Data Report (IDDR). According to the 2019–20 IDDR, there was a record 166,321 national illicit drug arrests in 2019–20, an increase from 153,377 arrests in 2018–19. The number of national illicit drug arrests has increased 96% over the last decade (from 84,738 arrests in 2010–11) (ACIC 2021). Most (88%) of the national illicit drug arrests in 2019–20 were for consumer related offences (Figure CRIM2).

Figure CRIM2: Consumer, provider or total national illicit drug arrests, by drug type, 2010–11 to 2019–20

This figure shows that in 2019–20, most consumer arrests were for cannabis (69,406) followed by amphetamine-type stimulants (43,428).

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Information related to criminal activity and contact with the criminal justice system is collected as part of the Ecstasy and Related Drugs Reporting System (EDRS) for people who regularly use ecstasy or other stimulants and the Illicit Drug Reporting System (IDRS) for people who regularly inject drugs.

Of the 2021 EDRS participants:

  • 10% had been arrested in the past year.
  • The most common self-reported crimes in the last month included drug dealing (23%) and property crime (18%).
  • A minor proportion (4%) of the sample reported a lifetime prison history (Sutherland et al. 2021a) (Table S1.18).

Of the 2021 IDRS participants:

  • 31% reported having been arrested in the 12 months preceding interview, increasing from 26% in 2020.
  • 3 in 5  (60%) participants reported a lifetime prison history, up from 56% in 2020.
  • The most common crimes reported in the last month were property crime (25%) and selling drugs for cash profit  (24%) (Sutherland et al. 2021b; Table S1.19).

Due to COVID-19 restrictions being imposed in various jurisdictions during data collection periods for both the IDRS and the EDRS, interviews in 2020 and 2021 were delivered face-to-face as well as via telephone. This change in methodology should be considered when comparing data from the 2020 and 2021 samples relative to previous years.

Data from the DUMA program indicate that drug use is common among police detainees. In 2020, 47% of police detainees had used cannabis in the past month and 45% had used methamphetamine. Over 4 in 10 (41%) detainees who had used an illicit drug in the past month (including heroin, methamphetamine, cannabis and ecstasy) reported that drug use was the reason for their current detention (Voce & Sullivan 2021).

Among police detainees who provided a urine sample:

  • Over 4 in 5 (82%) tested positive to any drug, and 46% tested positive to multiple drugs.
  • The most commonly detected drugs were amphetamine-type stimulants (57% of detainees), cannabis (45%) and benzodiazepines (25%) (Voce & Sullivan 2021; Table S3.59; Figure CRIM3).

In 2020, urinalysis data were collected in Quarter 1 (January–February) only, prior to COVID-19 restrictions being introduced. This should be taken into account when comparing 2020 data with previous years.

The Health of Australia’s Prisoners 2018 reports that overall, two-thirds (65%) of prison entrants reported using illicit drugs in the 12 months before incarceration, with the most common drug being methamphetamine (43%) followed by cannabis (40%) (Table S3.59; Figure CRIM3). The Australian Capital Territory (89%) and Tasmania (86%) have the highest rates of illicit drug use for prison entrants, while South Australia (58%) and the Northern Territory (40%) had the lowest (AIHW 2019) (Table S3.58).

In contrast, rates of drug use among the general population were substantially lower, with 1 in 6 (16.4%) people aged 14 and over reporting the use of any illicit drug in the past 12 months (AIHW 2020).

Figure CRIM3: Recent drug use among police detainees (2020) or prison entrants (2018), by drug type (per cent)

The figure shows that, in 2020, 82% of police detainees in the Drug Use Monitoring in Australia collection tested positive for any drug via urinalysis. Methamphetamine was the most common drug in positive urine tests (56% of detainees), followed by cannabis (45%), heroin (8%), and cocaine and MDMA/ecstasy (both 2%).

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Data from the 2019–20 IDDR found that:

  • There were 76,669 national cannabis arrests in 2019–20, with the number of arrests increasing 30% over the last decade (58,760 in 2010–11).
  • Cannabis (46%) accounted for the greatest proportion of national illicit drug arrests in 2019–20 and most of these arrests (91%) were consumer arrests.
  • While cannabis continues to account for the greatest proportion of national illicit drug arrests, this proportion has decreased over the last decade (down from 69% in 2010–11) (ACIC 2021; Table S1.20).

Data from the DUMA found that over 2 in 5 (45%) of police detainees tested positive to cannabis in 2020 (Voce & Sullivan 2021). Urinalysis data were collected in Quarter 1 (January–February 2020) only, prior to COVID-19 restrictions being introduced, this should be taken into account when comparing 2020 data with previous years.

Methamphetamines and other stimulants

Data from the 2019–20 IDDR found that:

  • Amphetamine-type stimulants (ATS) accounted for the second largest proportion (30%) of national illicit drug arrests in 2019–20. 
  • The proportion of arrests attributed to ATS has increased over the last decade (from 15% in 2010–11) (Table S1.20).
  • The number of national cocaine arrests has increased 543% over the last decade, from 839 in 2010–11 to a record 5,393 in 2019–20 (ACIC 2021; Table S1.20).

Urinalysis data from the DUMA showed that, in 2020:

  • Over half (57%) of police detainees tested positive to amphetamine-type stimulants.
  • Almost all (97%) detainees who tested positive to amphetamine-type stimulants tested positive to methamphetamine specifically.
  • Small proportions of detainees tested positive to cocaine and MDMA (2% each) (Voce & Sullivan 2021).

Urinalysis data for 2020 were collected in Quarter 1 (January–February) only, prior to COVID-19 restrictions being introduced (Voce & Sullivan 2021). This should be taken into account when comparing 2020 data with previous years.

Opioids, including heroin

Data from the 2019–20 IDDR found that:

  • Heroin and other opioids accounted for 2.0% of national illicit drug arrests in 2019–20.
  • The proportion of arrests attributed to heroin and other opioids has decreased over the last decade (from 3.0% in 2010–11) (ACIC 2021; Table S1.20).

Data from the DUMA found that over 1 in 5 (22%) police detainees tested positive to opioids in 2020 (Figure CRIM3). This included heroin (8% of detainees), buprenorphine (12%) and methadone (3%), and other (unidentified) opioids (3%). Urinalysis screening cannot distinguish non-medical use of pharmaceutical opioids (buprenorphine, methadone).

Urinalysis data for 2020 were collected in Quarter 1 (January–February) only, prior to COVID-19 restrictions being introduced (Voce & Sullivan 2021). This should be taken into account when comparing 2020 data with previous years.

Health and harms

The NPHDC includes a number of indicators regarding prisoner health and harms. In 2018:

  • 40% of prison entrants had ever been told they have a mental health disorder (including drug and alcohol abuse).
  • 10% of prison entrants experienced ‘a lot’ of distress due to alcohol, tobacco and other drug use, while 17% experienced ‘a little’ (AIHW 2019).

Further, data from the National Prison Entrants’ Blood Borne Virus and Risk Behaviour Survey in 2013 found that almost 1 in 5 (18%) prison entrants had shared injecting drug equipment in the previous month, placing them at risk of communicable disease (Kopak & Hoffman 2014 as cited in AIHW 2015). Less than 1 in 10 (8%) prison dischargees reported using a needle and syringe that had been used by someone else, while in prison (AIHW 2019).


Data from the Alcohol and Other Drug Treatment Services National Minimum Data Set showed that clients were referred to treatment services via police or court diversion in 8% of closed treatment episodes for clients’ own drug use in 2019–20. This is a decrease from 13% in 2018–19 (AIHW 2021a).

The NPHDC found that opioid substitution treatment (OST) was currently being undertaken by 7% of prison entrants and 7% of prison dischargees. Around 1 in 7 (13%) prison entrants reported ever having been on an OST (AIHW 2019).