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It is the National Offender Management Service's policy for all prison visitors found in possession of illicit drugs to be referred to the police. As a result of which in 2007-08 the police made 424 arrests of prison visitors the majority of which would have been for drug offences.
Irrespective of the subsequent action taken by the police, prisons will impose visiting bans and/or closed visits on the visitor concerned. The precise measures imposed will be decided locally, on a case-by-case basis dependant on the precise circumstances of the incident. These measures can also be imposed on the basis of suspicion, without the visitor found to be in possession of drugs.
These figures have been drawn from administrative data systems. Although care is taken when processing and analysing the returns, the detail collected is subject to the inaccuracies inherent in any large scale recording system. The data are not subject to audit.