As BBC Panorama will reveal tonight, Britain is losing control of its jails. An undercover investigation at HMP Northumberland has discovered that ‘the inmates are in charge’.

Gangsters rule over a culture of violence and drug-bingeing, fuelled by an open trade in cannabis substitutes such as (the newly-banned) Spice. There is so much Spice smoke in the air that one guard suffered a fit from passive inhalation.

Clearly, something is going very wrong in the prison estate. This news follows a similar expose at HMP Guys Marsh in Dorset, and two major riots at other establishments last December.

I suspect it will get worse before it gets any better. But I can’t help mentioning one pettifogging little imposition on all Britain’s lags that can only delay a happy outcome: the push to turn their confines into no-smoking environments.

Despite failed appeals in court (one claiming that a prison cell is in effect a ‘home’ and another that – given the restrictions on inmates’ ability to go outside – prisons were special cases) this became government policy in 2015 and has since been implemented at several jails across the country.

And, of course, the law of unintended consequences has struck again. At Dartmoor, for example, the cons have decided they may as well be hung for sheep as for lambs and the result has been the doubling in consumption of Spice.

As the Mirror related last year, a report by the prison’s Independent Monitoring Board had noted: ‘After a somewhat hesitant start, smoke-free seems to have benefitted many prisoners and staff. However the downside [has been] a sharp ­increase in the usage of “new psychoactive substances” (NPS) and seemingly also in its potency, resulting in near fatal casualties, frequent and costly hospitalisations, increased disturbance and some violent disorder on the wings.’

The report went on: ‘There has been a large rise in the number of recorded incidents dealt with by healthcare staff. Two thirds of incidents involved the use of NPS. There were several emergency hospitalisations and some close medical calls.

‘Since the introduction of smoke-free there was almost a doubling of rulings against prisoners in which they lose benefits, predominantly in NPS related offences, resulting in a large increase in the number of days added to sentences.’

This had become such a serious issue, claimed the paper’s sources, that a reversal of the policy was under consideration by ministers. But since then, no more has been heard of these deliberations. Instead, the Justice Minister Liz Truss has been struggling with the monumental task of structural reform.

This is a great pity and a missed opportunity. In times of crisis, innovation and adaptability become paramount. Truss should try reversing the smoking ban at Dartmoor to see if it can stop the Spice Age exploding. And if it does, draw the appropriate conclusion. Why blow off the bloody doors, just so nanny can make a point?

by Julia Dixon