Home > The impact of drug treatment on reconviction.

National Treatment Agency for Substance Misuse. (2012) The impact of drug treatment on reconviction. London: National Treatment Agency for Substance Misuse.

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This study compares the differences in the conviction rates of known offenders during the two years before their initial assessment for drug treatment and the two years after.

It presents the results of an analysis of data from the National Drug Treatment Monitoring System and conviction records from the Police National Computer. The data is drawn from a cohort of people who started a new course of drug treatment in 2006-07 and who had at least one conviction during the two years prior to their start date. The study was limited to trigger offences and soliciting (i.e. prostitution).
• The individuals retained in treatment for the entire two-years (4,677) showed an average 47% reduction in convictions
• Those who completed treatment successfully after being retained in treatment for six months or more showed virtually the same average reduction (48%) as those retained in treatment for the full two years
• Those retained for the full period reduced their convictions by three times more than those who dropped out of treatment, who achieved just 15%
• For all those who both completed treatment successfully and did not return during the period, the observed reduction in convictions is 61%.

While these figures cannot be interpreted as direct, quantifiable measures of a causal effect of drug treatment, the results suggest that exposure to treatment reduces recorded convictions and therefore offending, as the greater the successful engagement in treatment, the greater the observed reduction. This is most noticeable in opiate and/or crack cocaine users, who make up the majority of the cohort.

By focusing on engaging clients and promoting successful completions, drug treatment can help to maximise reductions in offending by individuals receiving help for their addiction, particularly if they use opiates and/or crack cocaine.

Item Type
Publication Type
International, Report
Drug Type
All substances, Cocaine, Opioid
Intervention Type
General / Comprehensive, Crime prevention
20 p.
National Treatment Agency for Substance Misuse
Corporate Creators
National Treatment Agency for Substance Misuse
Place of Publication
Accession Number
HRB (Electronic Only)
Related (external) link

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