Troubled teens sent to government-run boot camps were abused and assaulted by military personnel tasked with turning their lives around.

Two military staff have been through formal disciplinary proceedings, one step below a full court martial, over treatment they meted out to teens on the camps.

It has drawn criticism that the boot camps are not working and should be scrapped.

The six-week camps, officially known as Limited Service Volunteer (LSV) courses, are run by the New Zealand Defence Force in partnership with the Ministry of Social Development (MSD), aimed at helping young people at risk of being on the benefit long term, to find work.

Instead teens have been assaulted, mocked, sworn at and images of them have been used to make fun of them, according to evidence from military police who investigated the incidents.

The two defence staff were disciplined and removed from the camps because of physical and verbal attacks on trainees.

Their names, ranks and what arm of the defence they came from were redacted from records given to the Sunday Star-Times.

In August 2010, one of the defence personnel pleaded guilty to a charge of common assault and a charge of using threatening, insulting or provocative language while working at a LSV course at Burnham army camp. The charge included referring to a trainee as "f...... pig". The staff member was fined and reassigned out of the boot camps.

In August 2011, another military staff member at the Auckland airforce base Whenuapai repeatedly mocked up offensive images - including a modified image of a trainee being eaten by a shark.

At least one image was placed in an accommodation area.

When the trainee, who saw the images, objected, the military member said: "Do you want to have a go at me in here, come in here and have a go at me."

The defence staff member was found guilty on one charge of using threatening, insulting and provocative language and two charges of failing to comply with written orders and having unacceptable material in the NZDF environment.

They were also fined, assigned to extra duty and posted off the boot camps.

Limited Service Volunteer course staff can come from the army, navy and airforce. They work alongside civilian social workers and specialist staff.

Kim Workman, executive director of the Rethinking Crime and Punishment initiative, said a "values" clash between social workers and the military "can create a very unhealthy environment . . . it is also one of the reasons why boot camps don't work".

Putting already vulnerable teens into an abusive environment defeated the benefits of the course, said Labour social development spokeswoman Jacinda Ardern.

The defence staff running the camps should have been role models, she said.

"If these young people are putting effort into these programmes then they deserve to have people who are demonstrating good leadership skills," she said.

The Ministry of Social Development (MSD) defended the boot camps. It said the swift action against the abusive military staff showed the importance of strict behavioural guidelines while on the course.

Work and Income national commissioner Carl Crafar said: "The behaviour of these two individuals was unacceptable and this was clearly conveyed to the trainees."

The Defence Force said 106 staff have been involved in camps and there were only two who had broken rules.

Labour set up the boot camps - but Adern blamed the current National Government for the problems, claiming it had changed them from a totally voluntary scheme to one in which youth were ordered to attend.

GETTING THE BOOT

US state Florida banned state-run military-style boot camps in 2006 following the death of a 14-year-old who was beaten unconscious by drill instructors and then suffocated when ammonia tablets were administered in an attempt to revive him.

There have been at least 31 youth deaths in US boot camps since 1980, but not all camps are government-run. A work camp for juvenile offenders in Western Australia closed after 18 months at a cost of $3.4 million. Many inmates apparently asked to return to prison as they couldn't cope with the strict regime and isolation.

In 1997 a military-style intensive regime for young offenders in Colchester, England, closed after a year due to the cost. Initial evaluations suggested there was no improvement in reconviction rates for offenders taking part.