Driving a motor vehicle whilst under the influence of alcohol and other drugs significantly increases the risk of road accidents. According to data from the Australian Road Deaths Database from the Department of Infrastructure, Regional Development and Cities, in 2018 there were 100 drivers and motorcycle riders who were killed with a blood alcohol concentration (BAC) above the legal limit (excluding Victoria and Western Australia). This was a 32.9% decrease from the average annual number during the 3-year period 2008 to 2010 (BITRE 2020) (Table S1.13).
Among participants in the 2017 IDRS who reported recently driving a vehicle, three-quarters (75%) drove within 3 hours of using an illicit or illicitly obtained drug on a median of 24 occasions. Participants reported driving a median of 30 minutes after taking an illicit drug. The illicit drugs most commonly reported were crystal methamphetamine (43%), followed by heroin (39%) and cannabis (36%). Of recent drivers, 13% reported driving over the alcohol limit in the last 6 months (Karlsson & Burns 2018) (Table S1.14).
Family, domestic and sexual violence
Data show that incidents of family, domestic or sexual violence often occur in the context of alcohol and other drug use. For example, the 2016 Personal Safety Survey showed that of women who have experienced male perpetrated physical or sexual violence (assault or threat) in the past 10 years, around half reported that they believed alcohol or another substance contributed to their experience of male perpetrated sexual violence (ABS 2017) (Table S1.15).
Data from the 2019 NDSHS showed that 21% of Australians aged 14 and over had ever been verbally or physically abused, or put in fear by someone under the influence of alcohol (Table S1.23). Females were more likely than males to report their abuser being a current or former spouse or partner, while males were more likely to report their abuser was a stranger (Table S1.16).
A recent Australian study found that domestic and family violence incidents were significantly more likely than other violent incidents to involve drugs (Coomber et al. 2019). Respondents who reported the use of illicit drugs in the previous 12 months were 3 times as likely to report experiencing violence over the same period and the frequency of violent incidents was 6 times higher. The risk of injury doubled when respondents reported that the most recent incident involved drug use (Coomber et al. 2019).
Data from the Drug Use Monitoring in Australia (DUMA) program showed that detainees who reported dependence on methamphetamine or cannabis reported higher rates of domestic violence (Morgan & Gannoni 2020). Sixty-one percent of detainees who reported being dependent on methamphetamine reported recent violence towards a current or former intimate partner. This is substantially higher than the proportions reported for detainees who said they had used methamphetamine but were not dependent (37%) and detainees who said they had not used methamphetamine (32%). Similarly, detainees who reported being dependent on cannabis self-reported higher rates of domestic violence—58% compared with 41% for detainees who had used cannabis but were not dependent and 25% for detainees who had not used cannabis (Morgan & Gannoni 2020).
Illicit drug use within families
Parental drug use and conflict with parents are family factors that can increase the risk of drug use among younger people (Wilkins et al. 2019). Wave 17 of the Household, Income and Labour Dynamics in Australia (HILDA) Survey included a new set of questions assessing illicit drug use, including estimates for the use of any illicit drug in the previous 12 months. The collection of data for all family members allows the inter-relationship of illicit drug use among family members to be explored. Only findings for cannabis use have been reported—31% of respondents whose mother reported a lifetime history of cannabis use had used an illicit drug in the previous 12 months. This was 2.5 times higher than those whose mother reported no history of cannabis use (12.7%). Findings were similar when comparing results based on the history of cannabis use for fathers (Wilkins et al. 2019).
Homicide
The Australian Institute of Criminology’s (AIC) National Homicide Monitoring Program (NHMP) showed that there were 196 homicide incidents recorded in Australia in 2017–18 (excluding the Australian Capital Territory) (Bricknell 2020b). The NHMP draws information on the use of alcohol and other drugs by homicide victims and offenders from different sources, with data on victims based on toxicology and offenders based on an assessment by the police. In 2017–18:
- a higher proportion of victims had consumed alcohol than in 2016–17 (30% and 26%, respectively) and a lower proportion had used illicit drugs (27% and 29%, respectively) (Table S1.17)
- a higher proportion of offenders had consumed alcohol than in 2016–17 (25% and 20%, respectively) and a lower proportion had used illicit drugs (13% and 16%, respectively) (Table S1.17)
- in the 169 incidents where the relationship between the victim and offender was known, 3.0% were motivated by an alcohol-related argument and 4.1% were related to drugs (Bricknell 2020b).