18/09/2013 05:58 BST | Updated 17/11/2013 05:12 GMT

HMP Bristol Isn't an Isolated Case: There Is a Real Problem With Our Prison System

Even though they came unannounced, the inspectors that visited HMP Bristol in May could hardly have expected to encounter such a shocking institutional failure. The litany of mistakes they observed were detailed in a report released on Tuesday that makes for pretty grim reading. Filthy and overcrowded with some offensive staff, HMP Bristol is a hallmark of our broken prison system. It's hard to decide which of the findings is most disconcerting: the cockroaches, the shortage of adequate bedding, the "derogatory and abusive" language employees used or the denial of food as punishment.

Unfortunately, constructed as the system is, prisons like HMP Bristol are set up to fail inmates, staff and the general public alike. The prison population of England and Wales currently stands at around 84,000, a number that has risen by an average of 3.6% each of the last 10 years. With budget cuts falling upon the Ministry of Justice just the same as they are upon other departments, it is hardly surprising that capacity has failed to keep pace with the steadily rising number of incarcerations.

For each prison in England and Wales, the Prison Service provides a measure of the number of inmates that it feels it is able to accommodate to a decent standard given its capacity, something they call Certified Normal Accommodation (CNA). The most recent data indicate that more than half of our prisons are overcrowded, with some operating at more than 150% CNA. HMP Bristol was itself operating at a staggering 144% when the inspectors came knocking - certainly not an isolated incidence.

Those who think sentences are often too short would do well to remember this too: more than a third of prisoners in England and Wales are currently serving determinate sentences in excess of four years. On top of that, another fifth are either lifers or will serve time until they are deemed safe to return to public life (which could be never). Our incarceration rate was still153 prisoners per 100,000 population in 2010, and that is simply unsustainable. We win no prizes for having the second highest rate in Western Europe, and we have no right to be looking at the world beating US rate of 731 per 100,000 with any smugness whatsoever.

Problems like those identified at Bristol will always occur when resources are being stretched to breaking point like they so plainly are. Putting people behind bars costs money and during the course of a sentence an inmate's skills and ambition will both atrophy rapidly, especially those convicted of menial crimes. Anyone who has been out of productive employment for a sustained period of time can relate to the destabilising, demoralising effect these periods have on an individual, and prison is no different. In fact, it's probably worse, given appallingly cramped conditions, lack of gainful engagement and the potential to socialise with more hardened convicts.

There is no justice in making the taxpayer pay even more for these failing institutions when unacceptably high reconviction rates prove conclusively that prison is not the optimal solution to the problem of crime in many cases. No matter how much advanced warning HMP Bristol had had of the inspection, it still has very little power to stop many of its inmates coming straight back through its doors a matter of months after they are released.

Alternative sentencing isn't soft; it's just good sense based on such clear empirical evidence as this. We waste resources just to say we've taken an eye for an eye, a tooth for a tooth, and at the end of the day it is the victims of crime and the public at large who are left worse off than if we had dealt with criminality in a more sensible manner.

Prison doesn't act as a deterrent not because it isn't harsh enough - Bristol being an obvious illustration - but because it attributes an unrealistic level of rational calculation to each and every crime. Those in favour of tougher prison sentences seem to think that when someone thinks about committing a given crime, their thought process must go something like as follows: "I'm going to commit this felony. I know it's a felony and I know exactly how long I could get for it: 12 months... hang on the sentence has just been increased to 18 months...actually I think I won't offend anymore, ever".

The reason that logic sounds so preposterous is that it really is. Demonstrably so, otherwise worldwide crime rates would have a perfectly inverse correlation with severity of punishment. They don't.

It's not the fault of the staff that work in the system that seems to depend on the veracity of this argument; they are simply placed into a structure entirely unfit for purpose. Promised Liberal Democrat reforms of the penal system have - surprise, surprise - failed to materialise. Of all the U-turns and flippancy on their part, this may be the most harmful. Evidence based policy should never be so reliant on partisan assent, but it appears conservative antipathy to prison reform will obstruct the path to a more efficient justice system for some time to come.