"Nothing short of shambolic" uttered the softly spoken Sir Alan Beith MP, chairman of the Justice Select Committee, as he was passing judgement on the government's handling of court interpretation services.

This service may sound like a minor detail, but failing to provide an interpreter at the right time can lead to victims and their families, some of whom will have waited years for a case to come to court, see the trial collapse before their very eyes. Similarly, innocent people can languish in remand cells while the courts struggle to find an interpreter. These, according to the committee's report, have formed just part of the litany of failings in a poorly managed outsourcing process, which has wasted taxpayers' money and court time, while being unfair to victims and suspects alike.

This should not be happening. Much as interpretation services require the dedicated work of highly skilled professionals, the service itself is comparatively straightforward. You get the right interpreter to the right court at the right time. Sounds doable? Well, for the private contractor involved, it seems not.

Probation on the other hand, is an exceptionally complex service: how you get to the bottom of why someone is committing crime, supervise them in the community and help them turn away from a life of crime. The Probation Service is tasked with changing the lives of some of the most troubled people in our society, many of whom will have been in prison, experienced mental health issues, been victims of drug and alcohol abuse or grown up in a violent home.

If private firms can't even deal with interpretation services effectively, should they be trusted with the intricacies of navigating these far more difficult functions of the justice system? Mr Grayling certainly believes so, with a privatised probation scheme making up a key plank of his 'rehabilitation revolution.'

And for his privatisation model, the justice secretary has decided to look no further than the Work Programme, which he shepherded through as employment minister and which has been criticised for continuously failing to meet its targets. A similar 'payment by results' model will be involved for contractors, a concept which poses a host of difficult questions.

What is to stop firms 'cherry-picking' cases so they only work with those least likely to reoffend? And how do we measure success? If a young man who has served time for a serious violent offence stays out of trouble, but steals a bar of chocolate from a shop, will his supervisors lose out? Will breaches and reoffending, picked up by probation providers, be reported if those same providers lose money every time a breach occurs?

As has already been seen in our increasingly privatised prisons system, there is a risk that cost-cutting and maximising shareholders' returns will take priority over concern for public safety. Furthermore, any possible savings from the plan, however unlikely, would be dwarfed by Mr Grayling's extraordinary plan to build Britain's largest prison at a time when the prison population is falling and the Ministry of Justice has to make £2billion savings each year until March 2015.

If you have the impression of a Justice Department fumbling in the dark for new eye-catching schemes to showcase in the run-up to the election, you would probably be right. Indeed, the Justice Secretary refers constantly to the need to deliver his probation reforms before the country goes to the polls.

These are the wrong priorities and the wrong questions. Rather than focusing on who is managing the status quo, the government should instead be answering far more important questions that go to the heart of continued overspending and failure in our justice system. How do we prevent people from committing crime? What is the most effective way of stopping them doing it again? How can we restore public confidence? How much will this all cost and how do we build the most effective system we can with our ever decreasing pot of cash?

A pamphlet published last week by the Howard League for Penal Reform, 'Intelligent Justice', acts as a rallying cry for a fundamental reassessment of our justice system rather than a continual management of failure.

The pamphlet's authors, three of Britain's foremost criminologists, point out that a simple cost-benefit analysis of sentencing, though desirable and continuously avoided by politicians, is fraught with difficulty. Reoffending rates alone don't answer the question as to exactly why someone continued to commit crime.

The authors suggest instead that we look at the values we seek to encourage through the justice system and work from there. We should work to build a system that encourages people to buy into law-abiding behaviour, a far better means of cutting crime than compelling or cajoling individuals not to offend. They also point to initiatives in America, where some courts choose to celebrate someone's success in not reoffending rather being solely interested in those who have committed another crime.

Any solutions must, however, address the fact that the prison population in England and Wales has more than doubled since the mid 1990s, reaching a level unsustainable when budgets are shrinking. Talk of savings outside this context is meaningless and a fundamental reassessment of the way in which we go about cutting crime is needed to achieve them.

As yet, the government's 'rehabilitation revolution' involves little of either word, focusing more on how you crow-bar an ideological commitment to private sector delivery into the system rather than looking at what that system should be doing and why.

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