Bobby Cummines OBE was in and out of the prison system for 13 years and is now chief executive of UNLOCK, a Kent-based charity working with ex-offenders.
He believes criminals do not get enough practical help and advice during and after prison to change their attitudes and remove the incentives to re-offend.
"If you put a dog in a cupboard under the stairs and give it no training or love and affection, don't be surprised when it comes out and bites you," he said.
"Education was my liberation but my probation officer had time to work with me. He turned my life around.
"Now they've taken away the aftercare bit of probation and someone in their wisdom in the Home Office made the probation service a court policeman, who just enforces court orders."