Policy and practice briefingsPrisons and the criminal justice system

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People who commit criminal offences and enter the criminal justice system have higher rates of drug use and injecting than the general population. People with drug problems in the criminal justice system are often repeat offenders, and make up a significant proportion of prisoners. Adherence to the international drug conventions does not necessitate incarceration as a response to the use of controlled substances. Nevertheless, a significant number of offenders with drug problems are incarcerated for use or possession offences. Many others are imprisoned for other drug law offences or crimes, such as theft committed to obtain money for drugs. The complex health care needs of these individuals need to be assessed on prison entry.

As the average duration of a prison sentence for this group is a few months, they are a dynamic population with regular contacts with the community; this has implications for public health. Drug use occurs in prisons and also presents a public health and safety risk to prisoners and prison officers. The use of synthetic cannabinoids is an emerging issue of concern in some countries.

Response options

Alternatives to punishment: Encouraging drug-dependent offenders to engage with treatment can be an appropriate alternative to imprisonment. There is reasonable evidence for the effectiveness of some, but not all, of these approaches in reducing drug use and recidivism. More and better evaluations of the different models of interventions are needed.

Responses in prisons: Two important principles for health interventions in prison are equivalence of care to that provided in the community and continuity of care between the community and prison on admission and after release. This implies that all appropriate prevention, harm reduction and treatment services need to be provided within prisons and also particular attention paid to service provision around admission and release.

European picture

  • Opioid substitution treatment in prisons is reported by 28 of the 30 countries monitored by the EMCDDA (28 EU Member States, Norway and Turkey).
  • Detoxification, individual and group counselling, and therapeutic communities or special inpatient wards are available in prisons in most countries.
  • Infectious diseases testing is available in prisons in most countries, but hepatitis C treatment is rare. Hepatitis B vaccination is reported in 16 countries.
  • Needle and syringe programmes in prisons are reported in four countries.
  • Many European countries have partnerships between prison health services and providers in the community to ensure continuity of care on prison entry and release.
  • Preparation for prison release, including social reintegration, is done in most countries. Programmes to prevent drug overdose among opioid injectors are reported in five countries which provide training and naloxone on release from prison.

Summary of the available evidence

Interventions in prisons and the criminal justice system

Response option Quality of evidence

Opioid substitution treatment is protective against death in prison for opioid-dependent prisoners.

moderate quality evidence

Substitution treatment is also important in prison in reducing injecting risk behaviours.

moderate quality evidence

To prevent overdose death in the period directly following prison release, it is important that there is continuity of treatment in the community.

moderate quality evidence

Drug court programmes (in the United States, where the vast majority of studies have been conducted) can help people achieve financial independence and find employment or enrol in education and reduce recidivism.

lower quality evidence

There is some evidence that quasi-coercive treatment involving programmes diverting people with drug problems from the criminal justice system can be as effective as voluntary treatment.

lower quality evidence

Psychosocial treatments reduce the re-incarceration rates in female drug-using offenders.

lower quality evidence

For opioid-dependent offenders the use of naltrexone seems to help to reduce their re-incarceration rates.

lower quality evidence

Education and training interventions with take-home naloxone provision help to decrease overdose-related deaths after release from prison.

lower quality evidence


  • speedometer at highHigh quality evidence— one or more up-to-date systematic reviews that include high-quality primary studies with consistent results. The evidence supports the use of the intervention within the context in which it was evaluated.
  • speedometer at mediumModerate quality evidence— one or more up-to-date reviews that include a number of primary studies of at least moderate quality with generally consistent results. The evidence suggests these interventions are likely to be useful in the context in which they have been evaluated but further evaluations are recommended.
  • speedometer at lowLow quality evidence— where there are some high or moderate quality primary studies but no reviews available OR there are reviews giving inconsistent results. The evidence is currently limited, but what there is shows promise. This suggests these interventions may be worth considering, particularly in the context of extending services to address new or unmet needs, but should be evaluated.

Implications for policy and practice


  • The principles of equivalence of care and continuity of care require the provision of the same range of evidence-based interventions for people with drug problems in prison as in the community, provided by staff properly qualified for treating addiction (whether prison staff or outside professionals), and mechanisms to ensure continuity of treatment; this is especially important for those incarcerated for short periods.
  • Preparation for release should include activities to support social reintegration and training on overdose prevention — the provision of take-home naloxone should be considered.
  • Alternatives to punishment are recognised in the international conventions as a potentially valuable option for offenders with drug problems.


  • Prison settings may provide an opportunity to have a significant impact on morbidity, mortality and public health. Firstly, by engaging people with opioid problems in treatment, their illicit opioid use and risk behaviours in prison and overdose risks on release may be reduced. Secondly, by offering testing for infectious diseases to everybody on entry to prison and following up with treatment as needed.
  • Increasing the use of alternatives to punishment through review of the regulations that govern their application and addressing public and professional attitudes to their use may have the potential for improving long-term outcomes and reducing criminal justice expenditure.


  • UN/WHO guidance recommends the provision of harm reduction measures (needle and syringe programmes, condom distribution, safe tattoos) in prison, but this is currently rare — scaling up these programmes could make an important contribution to health improvement.
  • Studies are needed to improve the evidence base around alternatives to punishment, with particular attention being paid to the groups that can most benefit from these, and the stages in the criminal justice process at which they are best applied.

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