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Information on re-offending by juveniles by police force area is not available. Figures for re-offending by juveniles were published in May of this year in “Re-offending of Juveniles: new measures of re-offending 2000 to 2005 England and Wales”, but the data sets used do not enable analysis by police force area. The full report can be found online at
http://www.justice.gov.uk/docs/re-offending-juveniles-2000-05.pdf