Juliet Lyon: Our prison-building binge is a badge of national shame

The fevered rate of prison building, at a cost of £170,000 per place, is now set to propel the UK past most of our Eastern European neighbours for prison capacity. Overuse of custody has become a badge of political toughness rather than a matter for national shame.

With no crime wave to fuel it, how has this addiction to imprisonment taken hold so fast? According to a Ministry of Justice review, around 70 per cent of the increase in demand for prison places between 1995 and 2005 arose due to changes in custody rates and increased sentence length. A welter of criminal justice Acts, the creation of thousands of new offences and a raft of mandatory minimum penalties have all taken their toll.

Many more people are being received into prison than are being released.

In October this year, there were almost 6,000 people serving the new Kafkaesque Indeterminate Public Protection (IPP) sentences, 2,300 of whom were being held beyond their tariff expiry date, most with no means to show they present no risk to the public.

Add to this ever growing residual population the revolving door of petty offenders and staggering numbers on remand or recall, and you face an unsustainable prison population held at massive social and economic cost. Far from being a punishment of last resort, deprivation of liberty and incarceration is now so commonplace that 7 per cent of all children, at some time in their school years, will experience their father's imprisonment. In 2006, more children were affected by the imprisonment of a parent than by divorce in the family.

Prison has become a capacious net into which those let down by other public services fall. So no surprise that around three-quarters of people in prison suffer from at least two diagnosable mental health disorders and that learning disabilities and difficulties are rife.

The vast majority of people received into prison test positive for class A drugs and report a drink problem. There are more than 8,000 former service men and women in custody, many of whom will have been homeless prior to imprisonment.

Shocking reconviction rates show that we have got it wrong for victims and wrong for society. But reducing this new-found dependency on incarceration still won't be easy. It will take confident, authoritative politicians to shrink prison numbers. They will need to show how public safety and public health will be improved by using prison more sparingly.

Opinion polls show strong support for early intervention, community service, restorative justice, treatment for addicts and mental health care. People don't like unfairness and waste of scarce resources.

New, honest plans for proportionate justice and properly joining up social and criminal justice policies would make sense and be a welcome relief from a damaging prisons binge.