The Mary-Ann Leneghan case is distressing beyond words in all of its aspects. Yet reports from the court suggest that the young men who carried out these atrocities have no comprehension of how unspeakable their crimes were. They exchanged sniggers when evidence of a sexual nature was presented to the court. One of them - Jamaile Morally - is even reported to have whooped and said "yeah" as he was being led away.
It is difficult to believe that this level of psychopathology could be unnoticed by professionals. But this week's crushing news, that four of these people were on probation, appears to confirm that this is indeed the case. This latest awful crime comes in the wake of others that point to similar dereliction in this part of the criminal justice system, including the murders of John Monckton and Robert Symons.
For many people, the dreadful failure to comprehend the danger threatened by the young men who committed these acts of depravity conjures a particular picture. It is of an earnest, well-meaning, probation officer, doggedly meeting with her manipulative charge, offering endless encouragement and exhorting him to mend his naughty ways.
This hopeless picture of sad public-service do-gooding fuels vocal (yet unrepresentative) demand, in turn, for the criminal justice system to toughen up. If these men had been imprisoned for the petty crimes they had been convicted of, the logic goes, they would not have been on the streets to kill.
But the reality is even more mundane. Philosophical debate in the media about crime and punishment may remain simplistic. But there are even more simple explanations for what has been going on. The awful spate of murders by men on probation in London, for example, might be quite neatly explained by the fact that the London Probation Service has been in crisis mode for years.
This is because it tends to operate with anything up to 150 posts unfilled at any particular time. Criminals aren't sitting cosily with their probation officers and being molly-coddled in this part of the world. Far from it. Instead, probation officers have awesome caseloads and little opportunity for meaningful contact with anyone. The problem is no more complex than that.
At the time of the Monckton murder, when Damien Hanson was released on parole despite a risk assessment saying he had a 91 per cent chance of reoffending, the London probation service was ranked as the worst performing of all the 42 regional probation services in England and Wales. An emergency team was put in, to try to improve performance. There was some success in improving management structures, although not "offender work".
An inspection report expressed particular concern about "the quality of risk of harm assessments and supervision plans written on offenders".
Note the reference to written work. The needs of complex systems of course demand written reports. But some critics say the criminal justice system relies too much on documentation and not enough on frontline assessment by officers experienced in working directly with offenders.
Erwin James, in a weblog commenting on the Mary-Ann Leneghan case, says that information about people in prison or on probation is now largely about what courses on "offending behaviour" they have completed. Inmates, he says, find it much easier to manipulate a bureaucratic system, because they can tick the boxes and look like they are working hard on their rehabilitation when they are not.
As a reformed offender turned writer himself, James is worth listening to. "Monitoring and reporting on a prisoner's progress used to be a job that required considerable interpersonal skills and professional confidence," he argues. "Cases were discussed in depth and information shared ... Above all, before any recommendations were made, reporting staff made sure they knew the prisoner well. That was how they protected the public."
Now, he says, the emphasis is different throughout the system. People are not aware of how bureaucratic the process has become. Even that stalwart set-piece of the old movie - the Parole Board interview - is gone. It just doesn't happen any more.
In the light of these painfully obvious problems, it might be comforting to learn that the Government has done some sensible things. A recent restructuring, for example, slimmed the area probation boards down from 54 to 42 so that they matched with police, courts and crown prosecution boundaries. This rearrangement, all appear to be agreed, has helped.
But unbelievably, almost as soon as it was brought in, the Government began making plans to abandon it. For some while now, the Home Office has been nurturing an amazing scheme, whereby Whitehall takes over responsibility for providing probation services, appoints 10 civil servants to be regional commissioners of probation services, then invites the probation boards, along with voluntary groups and private companies, to bid for contracts.
The development of the scheme, announced by David Blunkett at the beginning of 2004, has finally been derailed by a large group of Labour MPs who lobbied for the elaborate and expensive plans to be greatly modified. No one now knows what Charles Clarke's new proposals are going to be.
It is good news for the probation service that it is not to be subjected to this sadly familiar piece of privatisation. But even so, much damage has been done. Its gestation of the two years has been fast elaborate, expensive - and largely secret, with the Home Office claiming that public debate might threaten its success (widely regarded to mean "put off prospective private partners"). So for two years now, the probation service has been working on, buried under caseloads, misunderstood and despised by the public, with absolutely no idea at all what the future may hold, and its professional bodies actually denied the information it asked for, let alone consulted meaningfully about the brave new world that is being built for them to operate in.
People have died horribly, have been maimed, and have witnessed the maiming of others, while the Government has played around with its favourite theories about the state and the market, almost certainly to little or no avail. It is all part of the struggle to secure Blair's "legacy", his last-gasp attempt to make the state into a commissioner rather than a provider of public services. His legacy, instead, is a nation with such men as these appalling killers, and such children as poor, impressionable, silly Mary-Ann, roaming the streets. As legacies go, it is not pretty.