LONDON - MAY 19: (FILE PHOTO) A prisoner reads a book in his cell at HMP (Her Majesty's Prison) Pentonville May 19, 2003 in London. A new report from the Prison Reform Trust (PRT) says overcrowding in Britain's prisons has been caused by tougher sentencing rather than an increase in crime. Since 1991, offenders of petty crimes are three times more likely to be imprisoned. (Photo by Ian Waldie/Getty Images)
