The Court of Appeal has upheld a High Court ruling that those arrested during a series of police raids in 2007 will have their cases heard by a judge, rather than a jury.
Eighteen people face a variety of charges under the Arms Act as a result of the raids. Five others are charged with participating in a criminal group.
Some of the accused had sought to be tried by a jury, but in December last year High Court judge Justice Winkelmann ruled that the case should be heard by a judge sitting alone.
The Court of Appeal decision, announced on Tuesday, has upheld that finding.
The trials are due to take place in Auckland in May.
