EIGHTY per cent of crimes in Cambridgeshire are committed by persistent offenders, who are to be targeted by the criminal justice system. That is one of three priorities for Cambridgeshire's Chief Constable, Julie Spence, who took over as chairman of the county's criminal justice board this week. According to the police, of the 150 people in the force area identified as persistent and prolific offenders, 33 were in Huntingdonshire and Fenland. They were estimated to account for more than 50,000 offences committed since last April - 12,600 of them in Huntingdonshire and Fenland. However, Mrs Spence has promised that when these offenders are released from prison, the criminal justice system would make sure they do not go uncontrolled. Mrs Spence has succeeded chief prosecutor Richard Crowley, who has chaired the board - made up of the courts service, CPS, police, probation, youth offending service and prisons - for two years.