Leading article: Principles and prison practice

The Justice Secretary, Ken Clarke, has prompted strike threats from prison officers by announcing that Birmingham Prison will become the first in the UK to be privatised. So far, the only private prisons in the country were built as such; this would be the first to be privatised, which is the reason for the furore.

The move is intended to provide value for money and reduce reoffending – both unimpeachable objectives. It must also be acknowledged that prisons in Britain, whether under public or private management, have a generally unimpressive record. They are expensive, compared with their Continental counterparts. Far too little attention is paid to education; drug use is rife, and reoffending rates are a national disgrace.

That said, however, we have qualms about extending the private sector further into prisons – a process begun under the last, Labour, government. Imprisoning criminals is done in the name of the state, and what happens in prisons should be the state's responsibility. Contracting the running of prisons out to a commercial company – such as the giant G4S, whose bid to run Birmingham Prison was successful – places these prisons at one remove from the state. However rigorous the inspection regime, that is one remove too far.

The trend towards deregulation has led to whole areas of the state being sold off or contracted out, and this looks set to accelerate, given the Government's desire to reduce the size and cost of the state. But a line has to be drawn somewhere. Defence and national security are clearly on one side – with the proliferation of private security firms in Iraq and Afghanistan a malign development. The administration of justice belongs on that side, too, which is why the privatisation of prisons is a matter of principle as well as practice. If commerce has something to teach in the matter of running prisons – which is not yet self-evident – the public sector should not be replaced, but required to learn.