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Volume 503: debated on Monday 11 January 2010

Prisoners Release

To ask the Secretary of State for Justice how many prisoners have been released in error as a result of (a) mistaken identity and (b) other errors in each of the last 12 years.

[Official Report, 11 November 2009, Vol. 499, c. 487-88W.]

Letter of correction from Maria Eagle:

Errors have been identified in the written answer given to the hon. and learned Member for Harborough (Mr. Garnier) on 11 November 2009. Certain figures in the table were incorrect. The correct answer should have been: (287035)

Prison establishments are required to report known releases in error to the Intelligence and Operations Unit in National Offender Management Service Headquarters. However, the Incident Reporting System does not hold records of these events in a format which can be interrogated electronically to obtain the specific information requested. Information on releases in error prior to 2005 could be obtained only by examining all miscellaneous incident reports manually at disproportionate cost.

The available information is shown in the following table.

Number of releases in error reported









2009 (to 30 September)


These incidents include three cases of mistaken identity; one in 2006 and two in 2008. In two cases the prisoner was returned to custody the same day and in the third he was returned within two weeks.

It should be noted that these figures have been obtained by a manual examination of paper records covering a variety of incident types and clearly only includes those errors that have been discovered. The figures are therefore subject to a margin of possible error.

The National Offender Management Service Agency is alert to the increase in 2008 and has taken action to tighten process and focus management attention on this area. Specifically:

All Release in Error incidents must now be reported immediately by telephone as a serious incident. Formal investigations are required in all cases and the learning from investigations has been acted upon.

Prison Governors and Regional Custody Managers have been required to review sentence calculation and discharge procedures and ensure additional managerial attention is given to this area.

Additional guidance has been given to prisons regarding fixed term recall arrangements.

More attention has been given to reporting this type of incident and it is possible that some of the apparent increase has been due to more consistent reporting.

Nevertheless, the number of releases in error remains very small as a percentage of total discharges (less than 0.05 per cent, in 2007, the last year for which discharge figures are currently available).