Cannabis availability
This section presents data on the availability of illegal cannabis, using a combination of law enforcement data and self-report surveys of people who use drugs. Analysis of illegal drug markets is complicated, and several caveats should be borne in mind when interpreting these data. Drug market factors (such as price, purity, and accessibility) are often inter-related, and it can be difficult to identify the cause of market changes. For example, some experts have attributed reduced availability of heroin in Australia in the early 2000s (the ‘heroin drought’) to key heroin seizures and arrests, while others suggest it was likely due to a shift in consumer preferences towards methamphetamine (Degenhardt et al. 2006, Harris et al. 2015). Changes in production and supply (for example, seizures) may also reflect law enforcement activity and not broader market trends. Nonetheless, these data provide a useful indication of the illegal cannabis market in Australia and trends over time. See Technical notes for more information on the data sources included in this section.
Production and supply
The production and supply of cannabis can be assessed using Australia’s Illicit Drug Data Report (IDDR), which compiles data on illegal drug arrests, seizures, and border detections across Australia (ACIC 2023). The most recent IDDR shows that cannabis is readily available to consumers. Cannabis accounted for over 1 in 2 (52%) illegal drug seizures in 2020–21, more than any other illegal drug. The number and weight of annual cannabis seizures has increased since 2011–12 but stabilised in 2020–21 compared with the previous year (Table 1.1).
Figure 1: Number and weight of national cannabis seizures, 2011–12 to 2020–21
Chart: AIHW. Source: ACC 2009 and 2013; ACIC 2018, 2019, 2020, 2021 and 2023. See Table 1.1.
Note: Includes only those seizures where a drug weight was recorded. Data may be double counted where there were joint operations between the Australian Federal Police and state/territory police.
Price and purity
Price and purity are key indicators of illegal drug markets as they are thought to reflect the availability of a given drug. For example, research on heroin shortages in Australia and the United Kingdom in the 2000s and 2010s has shown that reduced heroin supply impacted purity, price, and patterns of use (Degenhardt et al. 2006; Harris et al. 2015). Information on cannabis price and purity, as reported by people who use cannabis, is included in the Ecstasy and Related Drugs Reporting System (EDRS), the Illicit Drug Reporting System (IDRS), and the Drug Use Monitoring in Australia (DUMA) report.
All 3 surveys indicate that cannabis is generally medium or high purity. Most EDRS and IDRS participants who had used cannabis in the previous 6 months rated its potency as ‘medium’ or ‘high’ in 2023 (Sutherland et al. 2023a; Sutherland et al. 2023b). Similarly, ratings of cannabis purity among police detainees who had used cannabis in the previous month indicated relatively high quality in 2021 (median 7/10) (AIC 2022).
The price of cannabis is relatively stable, with a median price of $20 per gram in the 2023 EDRS and IDRS surveys (Sutherland et al. 2023a; Sutherland et al. 2023b). This is similar to the median price reported by police detainees ($17 per gram at the most recent purchase in 2021) (AIC 2022).
Accessibility
Cannabis is generally reported as being easy or very easy to obtain across various data sources, including surveys of people who regularly use stimulant drugs, people who regularly inject drugs, police detainees who use cannabis, and the general population (AIC 2022; AIHW 2024; Sutherland et al. 2023a; Sutherland et al. 2023b).
Data from the EDRS and the IDRS indicate that cannabis is readily available for people who regularly use illegal drugs. In 2023, most EDRS and IDRS participants who had used cannabis in the previous 6 months rated its perceived availability as ‘easy’ or ‘very easy’ to obtain (Sutherland et al. 2023a; Sutherland et al. 2023b). This has remained relatively stable over time and is consistent with cannabis availability ratings among police detainees (median 8 out of 10 availability rating in 2021) (AIC 2022).
Data from the 2022–2023 National Drug Strategy Household Survey (NDSHS) suggest that cannabis is increasingly easy to access among the general population. Around 1 in 4 (25%) people aged 14 and over said they were offered or had the opportunity to use cannabis in the past year in 2022–2023, up from 18% in 2010 (AIHW 2024). Perhaps unsurprisingly, people who had used cannabis recently or previously were more likely to have had the opportunity to use it than those who had never used cannabis (Figure 2).