The degree of civilisation in a society can be judged by entering its prisons,” said the great Russian novelist, Fyodor Dostoevsky. If he is right, then recent research into the state of the UK’s prison service should leave us all concerned.

An investigation by the Observer newspaper found that two-thirds of jails are providing inmates with inadequate conditions or unacceptable treatment. The findings were based on an analysis of hundreds of official inspections covering 118 institutions. It revealed a staggering 68 per cent are now providing unsatisfactory standards, with two in five jails considered unsafe.

The prisons minister, Rory Stewart, admitted that the condition of some jails is “deeply disturbing”, and that prisons are plagued by psychoactive drugs, and “increasing levels of violence committed by prisoners, and horrifying rates of self-harm”.

Experts have highlighted cramped cells, a shortage of staff and prisoners spending too long locked up in poor conditions. As a result, self-harm reached a record high of 42,837 incidents in the 12 months to September 2017, up 12 per cent from the previous year. Assaults reached a high of 28,165 incidents over the same period with serious assaults up by 10 per cent. Of these, 7,828 assaults were on staff. Perhaps the most worrying statistics apply to suicides: every five days someone takes their own life in prison.

How did we reach such an ‘uncivilised’ state? There are many contending factors. However, some things are clear. As part of the Government’s policies the prison service has been drained by privatisation with the operations of entire prisons turned over to companies such as Sodexo, Serco, and G4S. Some 18 prisons have been closed since 2010, while 14 per cent of the UK’s correctional services have been privatised.

In addition, the service has lost almost £1bn from its budgets since 2011, cutting 7,000 frontline prison officers. Nor does a promise to recruit an extra 2,500 officers offer much hope considering high staff turnover in this undervalued profession.

Perhaps the real problem lies in our society’s enthusiasm for incarceration as a way of tackling crime. Official data reveals that the number of prisoners in England and Wales recently rose to 84,255 – the highest imprisonment rate in Western Europe. To put this in perspective, just a quarter of a century ago in 1993, the prison population stood at 44,552.

Some people view the harsh conditions in our jails as a positive deterrent for those inclined to commit crime. It all depends on whether you believe imprisonment should be fundamentally about punishment or rehabilitation – or, as many argue, a complex mixture of both principles.

No one should underestimate the unhappiness, even misery, caused by every kind of crime to ordinary people. Some criminal acts are unforgivable. Prisons like Full Sutton house criminals who represent a real and on-going danger to the public. It may be that some will never be deemed safe enough for release.

But the vast majority of prisoners do not fall into that category. Drugs often lie at the heart of a career criminal’s journey from sentence to sentence to a totally wasted life. Nor should we forget the 21,000 mentally ill people, a quarter of the current jail population, who are currently imprisoned and not receiving the best possible treatment - therapies that might, over time, turn their lives around.

The perfectly understandable human instinct to punish rather than rehabilitate also comes at a high financial cost. Government statistics estimate the annual price of reoffending at a whopping £15bn. Proof that locking up lots of people does not deter criminality.

Partly because of this, Scandinavian countries like Denmark and Sweden have adopted pragmatic approaches some in the UK might see as ‘rewarding’ crime. Namely, they train prisoners in employment skills that allow them to get useful jobs after release. Such countries also seek non-penal forms of punishment wherever possible. The result is far lower levels of incarceration and lower crime rates.

A rational, humane and honest debate about our failing prison system is long overdue. And it could benefit the victims of crime most of all.