But Sensible Sentencing Trust founder Garth McVicar said he was "appalled" by the move, saying it would actually create an incentive to offend.
"My grandchildren are out selling firewood to pay for their computers to learn their computer skills in school," he said. "Why not take a shortcut and wait until you've committed a crime and then you get it all on the taxpayer?"
The prison will be the first NZ jail to put electronic gear into all standard cells. At other jails, only a few phones and computers are available in kiosks in common areas.
Serco Asia-Pacific operations manager Scott McNairn said the computers were part of a "responsible prisoner" approach, aimed at giving prisoners the education and skills needed to get jobs, homes, a driver's licence and other things they would need to live a law-abiding life after serving their time.
"Prisoners will be able to manage their own affairs, book their [family] visits, book their appointments, book their food," he said.
The Open Polytechnic has created interactive educational software designed to encourage students who may not have had a successful education experience and who have low language or maths literacy. The Howard League, which campaigns for penal reform, says 50 to 60 per cent of prisoners are functionally illiterate.
The software has been tested using tablets with 10 prisoners at Serco's Mt Eden Prison, where one inmate said his letters improved so much that his partner thought someone else was writing them for him.
Serco said Wiri prisoners would use fixed television screens that double as computers, each with a keypad and mouse. They will not have internet access.
A Serco spokeswoman said the company had "technology and security intelligence to assist us with monitoring the calls". "In terms of how do we ensure they don't conduct their criminal activities [by phone], that is a matter we will deal with," she said.
The company was providing the phones and computer hardware without charge, but prisoners would have to pay for calls at the same rates as in other jails, she said.
Corrections Department chief executive Ray Smith, who has been told by ministers to cut reoffending by 25 per cent by 2017, said the technology was "something I'd like to see across all prisons".
The Wiri jail is the country's first private prison mainly for sentenced offenders, housing low-, medium- and high-security (but not maximum-security) prisoners. Serco has a 25-year, $840 million contract bound by 1475 pages of conditions including $600,000 penalties for security breaches such as a killing or a riot, matched by bonuses of up to $1.5 million a year if it cuts reoffending to at least 10 to 15 per cent below the average of other New Zealand jails. Two fulltime Corrections Department staff have been posted at the jail to ensure it keeps all the conditions.
The contract is controversial because of Serco's mixed record in running similar facilities overseas. It was banned from public sector contracts in Britain for six months in 2013 after it was found to have been charging for electronic monitoring of people who were dead or in jail.
Mr Lotu-Iiga defended the policy of phones in every cell.
He said it would "not result in a substantial increase in the number of calls being made by prisoners nor changes to who prisoners are calling" but would "reduce the potential for tension in the shared areas around public phones as prisoners will not have to gather and wait to use them".
Prison for profit
• 960 beds at Wiri prison
• $840m total value of contract over 25 years (Source: Government)
• $270m construction cost (Source: Serco)
• $30m annual revenue (Source: Serco)
• $1.5m bonus every year if reoffending reduces (Source: Serco's contract)
