The man dubbed Tame Iti's "lieutenant" will be freed from prison on parole next month.
Te Rangikaiwhiria Kemara - along with the veteran Tuhoe activist - was sentenced to two and a half years in prison.
He has served nine months of his jail sentence after being found guilty of firearms charges in the High Court at Auckland last year.
The Parole Board said it was satisfied Kemara no longer posed a risk to the community.
The full decision and the board's conditions have not yet been released. He will be released on March 4.
Iti was granted parole last week.
Late last month Iti tweeted through family members his hope for release: "As it is Valentine's day ... I wonder if the parole board will show me some love."
During their sentencing in the High Court at Auckland last May, Justice Rodney Hansen said the only appropriate sentence could be one of jail. He described the rama or camps where people were trained in military exercises.
While defence lawyers had said the camps had been opportunities to learn bushcraft and skills to get security work, Justice Hansen said the jury rejected those explanations.
"In my view, they were utterly implausible."
He said it was a mystery why Iti had devoted so much time and money to developing "military capability" when he had been actively involved in Tuhoe negotiations before the Waitangi Tribunal.
He said while there were elements of the TV comedy show Dad's Army about the training, the intent was serious.
"As I view the evidence, in effect a private militia was being established. Whatever the justification, that is a frightening prospect in our society, undermining of our democratic institutions and anathema to our way of life."
He said the actions had damaged the "growing but fragile" trust between the Crown and Tuhoe that goes back to armed conflict in the 19th century.
Justice Hansen said there had been a focus on the damage done by the police raids in the Tuhoe region in October, 2007.
"That should not divert attention from the unlawful activities which necessitated the investigation in the first place."
Urs Signer and Emily Bailey were also found guilty of firearms charges and were sentenced to nine months' home detention, at their home in Parihaka, Taranaki.