The Crown says activist Tame Iti wanted to create a revolutionary army to bring self governance for the Tuhoe people at the point of a gun.
But a lawyer for one of the people accused of taking part in military-style training in Te Urewera National Park in the Bay of Plenty has questioned if what was going on was really criminal.
Tame Iti, Emily Bailey, Te Rangikaiwhiria Kemara and Urs Signer are charged with participation in an organised criminal group and unlawful possession of firearms in relation to police raids in the Bay of Plenty, Auckland and Wellington in 2007.
All pleaded not guilty when the trial began in the High Court at Auckland on Monday.
The Crown began its case on Tuesday morning. Crown prosecutor Ross Burns told the court up to 30 people took part in arms training at camps held almost monthly during 2006 and 2007.
Mr Burns told the jury the group was led by Mr Iti, an activist with the Maori iwi Tuhoe, and they planned to kidnap people, commit acts of sabotage and guerrilla warfare.
"They wore balaclavas or scarves to cover their faces. They didn't want to be seen by each other, let alone by members of the public.
"They trained in the use of firearms and they trained in what you will hear were identifiably military techniques."
The Crown said the group intended to use armed force to gain self-determination for Tuhoe in Te Urewera.
The court was shown undercover video surveillance of what Mr Burns said were some of the accused walking through the bush carrying firearms.
Texts and internet chatroom conversations were also shown to the jury which the Crown says shows that the group was planning to kill and that it was recruiting people willing to give their lives.
The Crown expects to call more than 80 witnesses over the next six weeks in support of its case.
The first will be the police officer who oversaw the installation of secret surveillance cameras in the camps in Te Urewera park.
The defence began its case on Tuesday afternoon. Mr Signer's lawyer, Christopher Stevenson, asked the jury if there really was a criminal group, or was it simply a group of people with different motivations and ideas.
"Was there just a bunch of people, the membership of which changed from time to time, with a myriad of motivations and ideas, thoughts and objectives?. And perhaps, with respect for some, with no idea at all," Mr Stevenson said.
"Suspicion's OK, it's a natural human trait but it can't run away on us. It must be checked. In a way in this case, you're the check. Suspicion that's not reined in breeds more suspicion and it finds its own proof."
Tame Iti's lawyer Russell Fairbrother said the Crown had to show the accused were part of an organised criminal group.
"To suggest there were a whole lot of others associated with it, and therefore at some great grouping of chaos in this country, is not what this trial is about. The Crown must first identify that there are three people who share this common objective, and then participate in it."
Charges against 13 others arrested in the raids were dropped last year after the Supreme Court ruled that some footage taken by covert cameras was illegally obtained.