A New Zealand Parole Board decision, released to the media today, said Namana had used his time in prison well, particularly lately.
However, it was deemed that there was still too much risk he could reoffend and the board has recommended he do more programmes during the coming year before applying for parole again.
Namana, now aged 38, has held a minimum security classification since July 2014 and been misconduct-free since the beginning of 2012.
Apart from a minor incident that led to a misconduct charge, for which he was admonished and discharged, there have been no concerns about his behaviour for some years now.
He completed the Drug Treatment Programme 6 in 2015 and went on from there to attend the Special Treatment Unit Rehabilitation Programme.
He began the programme at the beginning of 2016, was stood down at the beginning of December that year, restarted at the beginning of 2017 and graduated in November last year.
During the years he has achieved a number of unit standards in subjects as varied as introductory furniture making, carpentry, horticulture, engineering and laundry work, the decision said.
He is currently working with the Puppies in Prison programme and housed in the inner self-care unit.
While there, he has participated in 14 escorted outings outside the prison, mainly to do shopping for the unit.
He participated in a whānau hui in August last year and has had regular visits from his support people. These include the five members of his Circle of Support and Accountability, the majority of whom were members of a church.
Given the progress he had made, he sought parole.
In doing so his lawyer emphasised Namana's increased maturity and self-awareness over the last 19 years, which has seen him grow from an "angry violent youth to a skilled, reflective adult".
Namana is fortunate to have the loyal support of his support group who have offered him not only employment and accommodation post-release, but also a commitment to continue to support him in tertiary studies and in dealing with the issues which will surely confront him in the community, the decision said.
However, the decision said "while all of this was certainly impressive", Namana's history showed he struggled from time to time, in particular dealing with his emotions, and was assessed high risk of violent re-offending and moderate risk of general offending.
It also said he had had limited exposure to the community and the parole board was not satisfied it had reached the point where he could be safely released.
"We agree with the writer of the latest psychological report that his risk of reoffending is likely to be mitigated by engaging in a stepwise gradual reintegration pathway. He needs to be able to demonstrate that he can apply the skills learnt in the various programmes he has undertaken, outside the prison setting and in a variety of situations," the decision said.
Namana will be scheduled to be seen again in a year's time and before the end of May 2019, at the latest.
"We support his participation in guided releases, release to work and transition to Te Whare Oranga Ake, in the meantime."
An updated psychological assessment will be done before the next hearing.