Ken Clarke: Change rules on 'public danger' prisoners
Former justice secretary Ken Clarke says parole boards should have more power to free criminals jailed because they were a danger to the public.
He told BBC Radio 4's Today programme it was "absurd" to keep prisoners in jail beyond their original terms.
The Conservative MP described the UK's prisons as "overcrowded slums".
Mr Clarke abolished IPP (Imprisonment for Public Protection) sentences in 2012 as justice secretary, saying they were a "stain" on the justice system.
He told the Today programme there was a "ludicrous amount of incarceration in this country".
Mr Clarke said: "It is quite absurd that there are people who might be there for the rest of their lives, in theory, who are serving a sentence which Parliament agreed to get rid of because it hadn't worked as anybody intended.
"The trouble is this ridiculous burden on the Parole Board of saying they can only release people if it's proved to them that they're not really a danger to the public.
"No prisoner can prove that - you never know when people are going to lose their control, what's going to happen to them when they're released."
'Fear of public attack'
The IPP was introduced by Labour in 2003 and saw offenders serve a minimum jail term set by a judge, after which they could apply to the Parole Board for release. The board could only approve release if it regarded the offender as safe to rejoin the community.
It was originally intended to be applied when the most violent offenders were sentenced, with an estimated 900 people expected to be affected.
But it was applied much more widely, with 6,000 people serving the sentence at its peak.
Mr Clarke suggested the burden of proof be altered "so that the Parole Board only kept in those where there is some evidence that satisfied them that this person was a danger".
He added: "Let out the others; they finished their punishment they rightly got".
Justice Secretary Michael Gove has now ordered a review of the position of thousands of prisoners serving an IPP. Some 4,000 people sentenced with an IPP remain in prison, with nearly 400 having served more than five times the minimum term they were given.
Mr Clarke said: "You have a few thousand people still in our prisons with no idea when they're going to get out and a Parole Board that daren't let them out for fear of public attack if one of them does something serious and they've said they were satisfied that they were safe.
"Well, you can't be satisfied. Some of these people will stay there forever."
He called for improved rehabilitation work in prisons, saying the best chance for prisoners not to reoffend - providing they had no mental health or drug issues - was for them to "get a flat, a girlfriend and a job".
Mr Clarke added there was no room for initiatives such as training within prisons because of overcrowding, however.
'More of a risk'
Mr Clarke denied he and Mr Gove were "soft on crime", saying instead they want "the prison system to contribute to making Britain a safer and more civilised place" and pointing out that crime was down.
"The trouble is in prison, so long as they are overcrowded slums, so long as you don't tackle mental health problems, you don't tackle drug abuse properly, you don't give people some basic education when they haven't got any, and you don't prepare them for a job, you're actually toughening up some of these people and they're likely to be more of a risk when they come out," he added.
Speaking of the case of James Ward, a 31-year-old who remains in prison after being given a 10-month PPI in 2006, Mr Clarke said: "He shouldn't be there almost 10 years after he's finished the sentence".