Another factor is the relatively new Australian strategy of deporting NZ born prisoners on completion of the sentences. There are tales of kiwis who have spent years in Australia having their visas cancelled "on character grounds" for associating with suspected gang members.
No one knows how many of these deportees, many of who haven't the slightest connection with New Zealand except the chance location of their birth, will become offenders in New Zealand but a Senior Corrections official told me that the best guess was that a further three to four hundred prisoners could be added to our total. This equates to another medium sized jail and an annual cost to us all of thirty to forty million dollars.
This burgeoning jail population amounts to cruel financial pressure on the Corrections Department which has been on a fixed budget for years. Simply put, each extra prisoner means less money for such proven strategies as drug and alcohol rehabilitation, skills training, literacy tuition and post release mentoring.
Get all of these right and we'll heavily reduce the sky-high rate of re-offending which drives New Zealand's shamefully high rate of incarceration.
Judith Collins, now returning as Minister of Corrections faces a huge and expensive problem, but I for one have some faith that she can make a real difference.
It is easy to write off "Crusher" Collins as one editorial did as "penal populist", interested in little except "getting tough".
It is also unfair and untrue.
If you have visited Auckland Women's Jail as I have, you'll see newish tidy self-contained mother and child units where offender mums can keep their kids for much longer than the nine months that was allowed before Judith Collins came along. Officials at that jail will tell you that this innovation has changed the jail's atmosphere dramatically for the better.
I attended the first opening of a drug and alcohol rehabilitation unit some years ago at Auckland Jail (Paremoremo). This was to be the first of many and begins to address the awful fact that a very high proportion of crimes are committed when the offender is drunk or addicted to some drug or other.
There are now many such units. These started on Judith Collins watch too, as did the successful drug and alcohol courts in operation in Waitakere and Auckland.
A couple of years ago, Bill English described prisons as a "moral and fiscal failure", Later in the same speech he said: "It would be good if we could have ... less young people coming into the ... pipeline where they start with a minor offence and end up with a 10-year sentence."
Where and how this pipeline starts is well known and I've used this quote from British author Neil Gaiman before.
"The (private) prison industry needs to plan its future growth - how many cells are they going to need? How many prisoners are there going to be, 15 years from now? They found they could predict it very easily, using a pretty simple algorithm, based on asking what percentage of 10 and 11-year-olds couldn't read".
There are nearly five hundred people in jail right now for repeatedly driving without a licence. As the Howard League has demonstrated in Hawke's Bay, the great majority of these offenders, with personal attention and some literacy instruction, can get licenses and stay out of jail.
Let's hope Minister Collins is as creative this time around as she was before.