Examining policy options for preventing cannabis users from driving under the influence of cannabis
NDARC Staff
Wendy Swift
Other Investigators
Craig Jones, Don Weatherburn and Neil Donnelly (NSW Bureau of Crime Statistics and Research (BOCSAR))
Rationale
We currently have little information about the factors that are predictive of cannabis-intoxicated driving, and we know very little about the likely benefits of increasing the certainty or severity of sanctions or providing education campaigns warning about the potential dangers of this behaviour.
Aims
- what factors are predictive of the prevalence and frequency of driving under the influence of cannabis (DUIC), driving under the influence of cannabis and alcohol together (DUICA) and driving under the influence of cannabis and other drugs together?; and
- are there any likely deterrent benefits associated with (a) increasing the perceived certainty of being caught DUIC, (b) increasing the severity of sanctions if caught DUIC? and (c) providing factual information about the potential risks associated with DUIC?
Design and Method
Approximately 300 cannabis users were recruited to participate in a confidential, anonymous interview on their behaviours and attitudes towards DUIC. To be eligible, participants were aged 18 years or older, had used cannabis within the previous 12 months and had driven a motor vehicle within the preceding 12 months. Non-English-speakers and people with cognitive or psychological impairments that prevent them responding in a meaningful way were excluded.
The study comprised a cross-sectional analytic survey design. It incorporated a between-subjects factorial design to address the degree to which the certainty and severity of sanctions might reduce DUIC. Participants were presented with one of four vignettes giving a hypothetical situation where they were presented with the opportunity to DUIC and asked to rate their likelihood of driving under those circumstances. We hypothesised that, if roadside testing and harsher penalties for DUIC would exhibit a deterrent effect, those subjects who were led to believe that the certainty and severity of punishment are high would indicate that they were less likely to DUIC than those in lower certainty/severity conditions.
Benefits
Output
Jones, C., Donnelly, N., Swift, W., & Weatherburn, D. (2006). Preventing cannabis users from driving under the influence of cannabis. Accident Analysis and Prevention 38, 854-861.
Funding
NSW Cabinet Office, through the NSW Bureau of Crime Statistics and Research, NSW Attorney General’s Department