An independent Scotland would be different from the UK, wouldn't it?

There would be no nuclear weapons (apparently), no bedroom tax (possibly) and no fast-tracked membership of the European Union (allegedly). But on one issue at least, it looks like an independent Scotland would be (depressingly) exactly the same as the rest of the UK.

The issue is crime and punishment, an area of policy that has been devolved to Holyrood from day one but which continues to be based, like the policy in the rest of the UK, on one popular consensus: that prisons work. The consensus is profoundly wrong and yet it is still spouted in taxis, bars, offices and, sadly, police stations and courts all over the country. Admittedly, the Justice Secretary Kenny MacAskill has given the odd encouraging sign of change, but the core of justice in Scotland remains the lock and key.

If you doubt that - or hoped it might be different in an independent Scotland - look at the depressing plans for the new Barlinnie, outlined in The Herald yesterday. The prison currently sits on 134,000 sq m, but the new site will be around double that at anything between 200,000 and 300,000 sq m. It will be a huge expansion of Scotland's most famous jail and a staggeringly bad decision made in the face of pretty much all the evidence on prisons and reoffending.

And it is not the only recent sign of a flawed prisons policy. Just the other day, for example, at the height of the debate about the TV licence, it was revealed 70 people a year are sent to jail for not paying it. Really? Seventy people in a democracy sent to jail for not paying for a form of entertainment? That should be shocking, but it's not because we accept prison as punishment for even the most trivial offences.

And what about yesterday's furore over reading in prisons? The UK Ministry of Justice has denied it but it was claimed prisoners in England and Wales can no longer have books sent to them and if it's true, it is a staggeringly fatuous policy. You don't have to read books on prison reform to know prisoners need to be encouraged to read more, not less.

And again, Scotland is no better. A couple of weeks ago it was announced two Scottish jails have been picked to trial devices that stop prisoners accessing the internet. No doubt some inmates use the net and mobiles improperly but the more important point is that the internet can be used to help educate prisoners. The alternative is to keep them in a pre-internet dark age which will leave them unprepared to rejoin the world.

The benefits of the alternative - putting education at the centre of prisons - can be seen in the recent book by the economist Vicky Pryce (who has firsthand experience of jail after taking the speeding points of her then-husband Chris Huhne).

The book, Prisonomics, mentions a US study that looked at male offenders given custodial sentences in 2005 and the impact of educational and vocational courses on their reoffending. Although specific British research will be needed, it suggests prison education and vocational interventions could produce a net benefit to the public sector of between £2000 and £28,000 per offender.

The problem is the British penal system has not really tried the education experiment and the guiding principle remains punishment rather than rehabilitation despite the fact punishment is a model that does not work. Of the 47,000 Scots convicted in 2009/10, for example, a third were reconvicted within a year. We also know that if we stop building prisons and try an alternative, crime rates fall.

Sweden, for example, is closing several of its jails and its reoffending rate is half that of Scotland. The youth crime rate in Scotland has also fallen as the detention centres built by Labour have emptied.

The way forward from here is to truly put education at the centre of prisons and reward prisoners who do well. In Brazil, prisoners who read books are rewarded with shorter sentences, so why not go even further in Scotland? Why not reduce sentences by a day every time a prisoner reads a book and by a year every time he or she earns a qualification? Wouldn't that be more progressive and positive? Wouldn't that be better than scouring Glasgow and beyond for a 200,000 sq m site to build another prison that doesn't work?