Deborah Orr: The unexpected consequences of Labour's reforms to our criminal justice system

It is deeply painful to observe this weak and wounded government of ours, as it flails its way through its beleaguered third term. Its latest miserable attempt at buck-passing, led by John Reid at the Home Office, is confirmation that yet another Home Secretary has panicked at the state of his department, and seized the opportunity to play a cynical blame game.

After nearly a decade in power, this supposedly radical and reforming administration is more eager than ever to cover up its own systemic failures, by leaping on to the populist bandwagon parked at its door by the media, and blaming "soft judges" for the meagre tariff served up to sex offenders.

The latest scandal focuses on 24-year-old Craig Sweeney, a man that both expert opinion and common sense agree is unlikely ever to be able to function as a citizen. He has been sentenced to life imprisonment after he perpetrated a series of unspeakable crimes against a three-year-old girl. The Home Secretary is joined by the Attorney General in behaving as if his pathetic tariff of five-and-a-bit years is entirely due to the leniency of Judge John Griffith Williams.

In fact, the judge made it clear in his summing up that he thought it unlikely that it would ever be safe for this man to be released. This is correct. A desperate predatory paedophile such as Sweeney, whose inappropriate behaviour towards children has been evident since he himself was a child, has virtually no chance of responding to treatment. Many sorts of criminal can be rehabilitated. But the success rate among men such as Sweeney is poor.

In a decently functioning criminal justice system, therefore, his low tariff would be an irrelevance, an arbitrary figure arrived at due to considerations not relevant in his case. But as we have seen in the early release of other sex offenders, most recently Anthony Rice, our parole boards and probation services are just as swayed as the general public by these magic numbers.

Rice, with legal representation at his parole hearing, somehow managed to persuade the parole board that he'd been in prison five years "too long" because he'd served that much more than his tariff, even though the only truly relevant question was: Is this man still a danger to society? He killed Naomi Bryant shortly after his release, largely because parole boards, so much more bureaucratic now than they once were, are led by systemic concerns rather than human ones.

The crude populist argument is that "life should mean life". In a sensible system that worked properly, we could rest in our beds safe in the assurance that when that was really the case, then it would be so. Instead, the Government has lately desisted even from making an argument in favour of any aspect of the tariff system, let alone admitting that its own adjustments to it - particularly the discounts for those pleading guilty introduced in 2004 by a Home Office-appointed sentencing board - were utterly misguided.

The main arguments for the tariff system are well known. A prison community is - whether people like it or not - a little community. The community is by definition made up of lawbreakers, so it is imperative that there is a massively persuasive system that leads this combustible community to respect the authority of the institution they are in.

Thomas de Quincy was famously put in the debtors' prison of Edinburgh prison. Nowadays, similar systems of confinement-within-confinement still exist, but what those running prisons rely on to maintain authority is the idea that criminals can win time off for good behaviour. On the outside, the threat is imprisonment. On the inside, the promise is freedom. The parole system is necessary, even though it could certainly do with refining.

The trouble is that the Government's refining has not been much good. When Labour took power, it was rightly concerned by the long wait between charge and trial. This is, of course, entirely unsatisfactory for everyone concerned - including the victims, who have to spend many months in limbo before they are able to give their evidence. It means that witnesses can move away, lose contact or simply lose interest, and it means also that those charged must either remain in the community awaiting trial or be put under costly remand for extended periods.

It was also concerned by the number of wasteful non-guilty pleas. Because of some of the above considerations, alongside the effects of certain safeguards in the criminal justice system (such as the withholding of previous convictions), and the fact that time spent on remand has more privileges than time spent under sentence, it had become advantageous to even the most blatantly guilty defendants to try for a non-guilty plea. Obviously, this was a problem that needed to be addressed.

Among the various suggestions that came up for dealing with this difficulty were some that the judiciary stubbornly defended (which goes some way to explaining why the Government is less concerned than it should be about hanging the judiciary out to dry). A number of ideas fell by the wayside - mostly but by no means always quite rightly. But the need to make cynical pleas of not guilty less attractive to criminals remained. One of the ways in which the Government hoped to achieve this was by rewarding those who make an early plea of guilty.

It was a worthy aim, but a crude and counter-intuitive mechanism. Instead of punishing criminals for their perjury, it rewards them for their lack of it. In cases like Sweeney's - in which a plethora of evidence ensured a guilty verdict anyway - it provides a vast and dangerous free gift (in Sweeney's case, a six-year chunk off his tariff). One is forced to conclude that other considerations - such as the Government's concern with minimising the inexorable rise in the prison population - influenced this mad bit of ready-reckoner sentencing, whereby the more terrible the crime, the greater the prize for admitting to it.

Beyond all these considerations, there is the sense in sex offender cases, above all others, that a system geared towards treating criminality as a human failing that can be managed centrally through policy and procedure is not appropriate.

Sweeney's defence counsel claimed that his crime had been committed "on the spur of the moment". This is nonsense. He turned up at the home of a woman he had known before, having discharged his previous sex-offender sentence two days before, and snatched her daughter while she was on the phone. The abduction only ended when he became involved, by coincidence, in a police car chase.

"On the spur of the moment" does not mean "spontaneously" here. It means "with self-deceiving and uncontrollable compulsion". Nothing but containment can protect society from compulsions such as these. No set of number-crunching guidelines can ever be devised that can calculate the course of a sex offender's sentence.

d.orr@independent.co.uk