The Royal Commission into the attack on two Christchurch mosques last year has interviewed the terrorist who killed 51 people.
Brenton Tarrant has been convicted of the murders, along with an additional 40 charges of attempted murder, all relating to the shootings at Masjid Al Noor and Linwood Islamic Centre on March 15.
His shock guilty pleas in March included admitting engaging in a terrorist act.
A Royal Commission is investigating his activities in the lead-up to the mass shootings and this has included interviewing the convicted terrorist in private at Auckland Prison.
Commissioner Jacqui Caine said it was a "carefully considered decision driven by the need to observe natural justice" and with the ultimate goal of providing answers to the New Zealand public.