Rehabilitation for some of the most serious sex offenders in jail has been branded "woefully inadequate" by opposition parties.
Figures show just a 6% difference in reoffending between sex offenders who do a treatment programme and those who don`t.
Liberal Democrat justice spokesman Robert Brown obtained the figures through Parliamentary answers. It comes after former prisons chief inspector Andrew McLellan warned in his final report that there are not enough rehabilitation places - and many of the most serious offenders will not sign up.