The government is caught in a penal policy mess of its own careless making. It knows it too. Yet its response to a prison population standing at 82,319, and a system buckling under the strain, is technocratic fix. Equipped with Lord Carter’s latest report, Jack Straw ponders a sentencing commission that may bring use into line with capacity; is devoting £2.3bn to three Titan jails that next to no one (not even, one suspects, Straw himself) thinks a good idea; and urges sentencers to use alternatives to short spells of imprisonment. He then hopes for the best and that the topic slips back below the media radar screen. A politically faltering government can it seems – in this high-voltage policy field – do little else.

But it can. The current crisis is testament to the fact that the English penal system lacks a coherent public philosophy – a story about why and whom, and how and how much, we punish that connects with sentiments that have some purchase within English society. Such a philosophy starts from where ‘public opinion’ recognizably is. But it need not end there. Given the condition, cost and manifest failings of English prisons today, our society requires a philosophy that provides a convincing rationale for radically reducing the harshness and scale of the present penal system – and for that milder and smaller system. Penal moderation is the best available candidate we have for such a philosophy.

Penal moderation brings together three ideas: restraint, parsimony and dignity. First, it seeks to instil a sense of caution and restraint in how our society talks about and delivers punishment. In so doing, it connects with the moral ambivalence that many citizens feel towards punishing – the fact that punishment is capable of evoking anger, resentment and a passionate desire to inflict harm on the criminal wrongdoer, but also calls forth feelings of shame, regret and forgiveness, invoking responses which seek repair and reconciliation.

Second, penal moderation recognizes that punishment is a tragic institution – destined to disappoint because the levers that conduce individuals to conform lie mainly beyond its control. It recalls the fact that prison is a perennially failing social institution about which it is wise never to be sanguine. The watchword is thus parsimony. Penal moderation focuses public attention on the question and benefits of a minimum necessary penal system and enjoins us to treat, and use, the prison as an institution of last resort.

Third, penal moderation requires a penal system that treats with dignity all those who are brought under its care and control; recognizing that offenders are and remain citizens and must be treated as such. This means that basic human rights can and should apply within penal settings, and that harm reduction – a culture of moderation – is embedded within the routine practices of penal institutions.

How though to connect penal moderation with the present trajectories and temper of penal policy? It can, first of all, sharpen our sense of how that policy has erred. The opposite of moderation is not simply expansion, but excess – an accurate description of how our society responds to crime today. Historians can be left to puzzle over why a government that inherited and sustained falling volume crime levels has rhetorically behaved as if crime were not just a social problem, but the social problem; enacted more criminal justice legislation in 10 years than was passed in the previous 100, and introduced over 3,000 new criminal offences.

The current penal crisis is, however, a legacy of that restless excess. The result is a society that appears altogether too comfortable with banishing thousands of – typically young, poorly-educated, mentally-troubled and drug-dependant – men and women to institutions of penal coercion. The government would be prudent now to steer a less over-heated and prison-centred course – and to lead in fostering a public climate that makes this more rather than less politically feasible.

Penal moderation assists here by reminding us that it didn’t have to, and doesn’t have to, be this way. Since 1995 prison numbers in England and Wales have risen by 60 per cent. In France over that period they rose by 1 per cent, in Canada they fell by 11 per cent – facts that Lord Carter tellingly brought to Straw’s attention. Finland has also in recent years radically cut its prison population. Norway has long sustained a mild penal system, as has Germany. Closer to home, the minority SNP government in Scotland is consciously carving out a moderate penal alternative to that prevailing south of the border – modelling itself on (mild) Sweden rather than (harsh) England.

Many of the conditions that underpin moderate penal systems do not travel easily: a commitment to egalitarianism and generous welfare systems; keeping penal policy in the hands of trusted professionals not elected politicians, and relative media inattention to crime and punishment. One however might – namely, a sense of national shame and the political will to call and act upon it. The art of penal moderation may lie in knowing how to tap into, and work with and upon, the feelings of popular unease that punishment can provoke.

Over the past 15 years penal policy has been driven by the most strident voices to be gleaned from opinion polls, focus groups or the tabloid press. Yet this rests on a partial reading of what is known about public sentiment towards crime and punishment. There are those whose daily lives are blighted by crime or whose experience or worldview makes them angry enthusiasts for ‘tough’ punishment. But there is also evidence that the majority of people have little experience of crime, rarely think about it from one day to the next and, when prompted to do so, express ambivalent feelings about the proper response to it. These are not people minded to send a donation to a penal reform group. But when given actual cases to ponder, they sentence much like, or more lightly than, real sentencers. They view prison as futile and back the idea of offenders repairing the damage they have caused. They also know a waste of money when they see one.

Cultivating penal moderation means speaking for this often silent and – in an over-heated media culture – silenced ambivalence towards punishment. It requires political leaders with the courage and skill to make these sentiments publicly explicit and allow them to inform how our society thinks about and delivers punishment. This entails the government doing more than tweaking policy outcomes within the frozen parameters of current politics; it means adjusting those parameters and giving voice to a new public vocabulary. One may progress within those constraints by highlighting the economic costs of continuing to expand the prison estate in ways that appeal to the public’s hard-headedness. But there may, ultimately, be more to be gained from exploring the progressive resources of moderation; opening the hearts and minds of citizens who understand England as a tolerant, forgiving, pragmatic nation – a home of sweet moderation – to the prison system that has been so thoughtlessly swollen in their name.

This may be hard politics, but it is also good politics. The prize is penal policy which is the confident expression of a coherent public philosophy of why, when, whom and to what end our society punishes – policy that directs scarce resources to where they are most needed and useful, rather than stumbling from one policy fix to the next.