Corrections staff say Judith Collins' clamp on bail is keeping more inmates in jail.
Corrections officials say the prison population has unexpectedly risen this year, and they believe one of the causes is hardline bail laws introduced by Judith Collins when she was Justice Minister.
The total number of inmates in New Zealand's 17 prisons had been forecast to steadily decrease between 2010 and 2016 as a result of a falling crime rate, increased use of community sentencing, and a stronger focus on reducing reoffending.
But in a briefing to new Corrections Minister Sam Lotu-Iiga published this week, Corrections officials said: "While these forecasts were reasonably accurate up to the end of last year, the current year has featured an unexpected climb in prison numbers, particularly affecting the remand population."