Corrections has admitted it has acted outside the law by confining women to to their cells at Auckland Women's Prison for more than 23 hours a day.
Women at the jail, 67 percent of whom are Māori, have been denied their minimum entitlement to one hour out of their cells for exercise on multiple occasions this year, including 16 times in just a two week period.
That sparked an internal Corrections review which was released this week.
It described a punitive culture at the jail, dysfunctional management and a lack of health-staff to care for the women inside.
RNZ investigative journalist Guyon Espiner, who broke the story, asked Corrections' Chief Custodial Officer Neil Beales why they are breaking the rules at the country's largest women's prison.