New Zealand has one the highest imprisonment rates in the developed world, and despite a target of reducing re-offending by 2017 by 25% (that won’t be met) $1 billion more will need to be spent in the next five years to house all the prisoners.

The public psyche is punitive, with pressure on politicians to lock more offenders up for longer. That will cost more – and that cost is not just borne by the country (that is, all of us), there is a high cost to families and children affected by imprisoned parents.

New Prime Minister Bill English wants to apply his ‘social investment’ theories to prison numbers and re-offending rates. He has signalled a change in approach by removing Judith Collins as Minister of Corrections and replacing her with Louise Upston, who is also now Associate Minister for Tertiary Education, Skills and Employment.

Fixing the  lack of education and work skills that are prevalent in the prisoner population is an important part of rehabilitation and reducing re-offending.

The Government doesn’t just have to turn around rising imprisonment rates, it also has to turn around punitive public preferences. Neither will be easy.

Dr Jarrod Gilbert at NZH: Bill English faces tough job shifting the ‘lock ’em up’ penal policy

For a number of years Bill English has quietly championed a prison reform approach that should appeal to fiscal conservatives and social liberals alike. As prime minister, he now needs to sell it.

At stake is a billion dollar spend on a new prison caused by a prison population that recently hit 10,000.

In 2012, the government and the Department of Corrections set a bold target of reducing reoffending by 25per cent by 2017.

They are going to fall well short. Undoubtedly, many people will make a big deal of that failure, and perhaps that’s reasonable, but it ought be applauded for its bold intent.

It was the ambition of the target that challenged corrections staff – from policy analysts to prison guards – to fundamentally rethink what they were doing. Instead of simply containing prisoners until their release, they were instructed to think about creating an environment and initiatives that rehabilitate them.

It was never going to be a quick or easy thing to fix, but rehabilitation needs to be addressed.

Nearly three quarters of released prisoner were reconvicted of an offence within five years, and more than half were returning to prison.

In many cases if the underlying causes of crime aren’t resolved then offending is likely to continue.

More importantly, reducing reoffending wouldn’t just reduce costs, it would also mean fewer victims of crime. There is perhaps no clearer example of a classic win/win.

That’s something that the public need to understand.

On this basis, the government launched a reform agenda, but it hasn’t taken the country with it. And this is a mistake. Without building a broad public consensus on the approach’s goals and merits, it is at risk from moral panics and knee-jerk politics.

Our base instinct to punish criminals is natural and punishment is an important function of prison.

Lock-em-up proponents tend to be more vocal, more pushy for more imprisonment.

But often there will be no sentence long enough to placate distressed victims or their loved ones, so as a society we must weigh-up those desires with the interests of the public good.

Media play a major part in this. It’s common for them to push the victims of crime to speak after sentencing, and in most cases unsurprisingly they usually say sentences were not sufficient. This just feeds the longer sentence pressures on politicians.

And here’s where we need to start the conversation and build a consensus around the balance between punishment and rehabilitation.

Extending the debate beyond punishment may not be easy. New Zealand has been sold the idea that longer sentences are the solution by both major parties for years.

Populist tougher sentence policies pander to what voters seem to want.

Penal populists say harsh sentences act as deterrence by making people think twice before committing crime. Deterrence arguments aren’t without merit but studies show that likelihood of apprehension is a far greater deterrent than severe punishments.

So wouldn’t an extra billion dollars be better spent on policing rather than on prisons?

But media and public pressure works against this.

When Philip Smith escaped to Brazil in 2014, for example, there was an immediate clampdown on temporary releases that allow prisoners to work outside the wire in paid employment.

Despite the escape being a consequence of corruption rather than policy, the Department of Corrections feared a public backlash and restricted temporary releases even though they were widely seen as a successful rehabilitation tool.

One high profile escape adversely affected many others.

Having removed Judith Collins from the Corrections portfolio, English has very publicly signalled that the harder-edged and populist approach does not curry his favour.

But can he change public attitudes in the way Judith Collins and others so cleverly played up to them?

Can English convince the country that although the Department of Correction’ re-offending target won’t be met, its modest gains and the change of thinking it represents is nevertheless the best hope of bringing the prison population down?

That won’t be easy.

I don’t know the answer to that; the punitive approach in the New Zealand psyche is so strong we’ve become one of the most imprisoned populations in the developed world without even flinching.

The loudest calls are for even longer prison sentences.

Do we really want more prisons?

Or can we see the sense in more policing, more rehabilitation and less offending?

One thing that Gilbert doesn’t mention is drug and alcohol links to a lot of offending. Addressing addictions is a critical part of rehabilitation.