The father of one of the prisoners injured at Serco's Mt Eden facility says the Corrections Department should come down harder on the company.
Corrections announced yesterday it was appointing a director to manage the day-to-day running of the prison and would impose financial penalties on the prison's operator Serco.
The prison has been the subject of a string of complaints about organised fights, contraband, prisoner injuries and the death of one inmate.
Mike Littleton, whose son was injured in what Corrections described as a fall from a cell block balcony in February, said the department had taken a step in the right direction.
"You know the penalties, I actually think should be more severe, but pending an investigation, because there's been a lot come out and I think there's going to be a lot more come out of what's been going on," he said.
But Mr Littleton doubted the department would end up taking tough action against Serco.
"They've made a decision and they don't want to look bad by having to pull the contract out."
The Department of Corrections said it would wait for the results of a full review before making a decision on the future of Serco's contract.