Aim
To examine the specific deterrent effect of offender supervision on the risk of a further offence by persons convicted of amphetamine use and/or possession.
Design
Observational study of two groups matched on a wide range of factors using augmented inverse probability of treatment weighting.
Setting
New South Wales (NSW), Australia.
Participants
A total of 2099 persons convicted of amphetamine use and/or possession and placed on either a supervised good behaviour bond (1004) or a bond without supervision (1096).
Measurements
Conviction for another amphetamine use/possession offence, any drug offence, assault or theft within 48 months free time after the index court appearance.
Findings
Only two of the treatment estimates were consistent with a deterrent effect. Where the outcome was an assault offence, the estimated reduction in risk of re‐offending was 1%. Where the outcome was a theft offence, the estimated reduction in the risk of reoffending was 0.07%. Neither result was statistically significant. The coefficients measuring the effect of supervision on the remaining two outcomes (use/possess amphetamine and use/possess any drug) were both positive and not statistically significant.
Conclusion
Correctional supervision does not appear to have been effective in New South Wales, Australia, in reducing the risk of reoffending among people convicted of amphetamine use/possession.