Why parole needs changing

The Press has a story on paroled child killer Robin Pitney, which highlights the problems of the current parole system.

In 1992 he was sentecned to life imprisonment for stabbing to death an 11 year old boy. It was a random unprovoked attack.

The Parole Board let him out at the earliest possible date in 2002. After less than a year he reoffended again. Now he was recalled to prison, but only for a few months, and then released once again on parole.

And surprise surprise he is now assaulting women.

Why did the Parole Board re-release him after only a few months, when it was clear he was not rehabilitated?