Prison managers now attend Parole Board hearings along with prison officers to give information about inmates seeking parole.
The Government says the move will help the board make more accurate assessments and enhance public safety.
Corrections Minister Judith Collins says the change goes a long way towards ensuring the Parole Board has all the information it needs to accurately assess risk of reoffending.
She says the presence of a unit manager at parole hearings will also provide additional support for prison officers.
Ms Collins says the system has been operating for a month and the board has noticed an improvement in the information it receives.
Garth McVicar, from the Sensible Sentencing Trust, says many inmates use standover tactics against prison staff who may then be afraid to give honest appraisals at parole hearings, and a manager's presence could mean more accurate information is given.