Minister of Corrections, Kelvin Davis missed a great opportunity when National leader Simon Bridges started whacking him around the head over the weekend with the latest report on the population explosion in our prisons.

Instead of playing Bridges game, which was to attack the Government for not going ahead with National's planned 3,000 bed mega-prison, Davis could have reset the agenda by embarrassing Bridges with some of the other statistics in the report.

Bridges was obsessed with the Justice Department prediction that inmate numbers would rise by 4100 to 14,400 over the next decade.


Where would they all fit, he wailed.

What Davis could have fired back was that instead of building a $1 billion new prison, the prisoner accommodation crisis could be cured for free by repealing National's populist Bail Amendment Act, 2013, which had rapidly over-filled the gaols with "innocent" men and women awaiting trial.

The report spells this out. In the 2018 fiscal year, of the 11,201 total prison population, 3,455 were awaiting trial.

These accused were locked up at our expense, on average, for 75 days each while waiting for their day before the judge. Around one in every four were found not guilty.

In other words, in the fiscal year just ended, thanks to the 2013 exercise in political populism, 819 innocent New Zealanders were incarcerated for around 75 days each, found not guilty, then released back into the world, without a sorry or compensation, for the lost jobs, lost tenancies, family disruption and the like, they'd suffered.

Also, of those convicted, the report notes that only 12 per cent received a prison sentence.

By 2027, it will be much worse. If nothing is done, 5,457 of the 14,399 projected prison population will be people, removed from the community while awaiting trial.

The Government, which like the National Opposition, continues to play footsie with the law and order lobbyists, has tried to have a bob each way. Instead of going ahead with National's planned 3,000 bed, $1billion megaprison at Waikeria, it has opted for a 500-bed high security facility, with a 100-bed mental health facility alongside.

Reformers such as criminologist Roger Brooking argue against the need for either the megaprison or the Labourlite substitute. He points out that the prison population could be cut by 30 per cent in six years simply by repealing the 2013 bail amendment act and by releasing short-term prisoners after serving half their sentences.

The 2013 act was passed in the hysteria fuelled by the "Sensible Sentencing" hardliners following the murder of Christie Marceau by her mentally ill former friend Akshay Chand while he was on bail for an earlier incident when he'd kidnapped her.

He was on bail because a medical professional had advised a judge that his anti-depressant medication removed the need for custodial remand. If ever there was an example of hard cases making bad law, this was it.

Parliamentarians were advised by officials the tougher bail laws would only increase the number of prison beds for remand prisoners by around 50 to cater for the expected 350 extra detainees a year. They were ill-informed. It's now 3,455 and rising fast

At the time there was cross-party support. Current Justice Minister Andrew Little was a fan as was then Labour Justice spokesman Phil Goff, who called it a "fairly soft measure."

The present Government seems to be repeating the same pattern that marked its predecessors. In 2011, with our incarceration rate steadily climbing to reach the disgraceful level of third world countries like Gabon and Namibia, Finance Minister Bill English in 2011 conceded to a Families Commission forum that prisons were "a moral and fiscal failure."

He later said he hoped the 1000-bed Wiri prison would be the last because they're very expensive – costing $250,000 a bed in capital costs and $90,000 per prisoner to run.

Famous last words. As out-going Prime Minister in 2017, he dumped the $1 billion Waikeria mega-prison project onto the incoming Ardern Government's lap.

Like English, Little now describes the old "tough-on-crime" regime a failure, but his call for a "national conversation" is depressingly indecisive. At the very least he could show he means business by repealing the 2013 amendment act. That would be a good conversation starter.