The Department of Corrections says it works hard to integrate prisoners back into the community but needs the help of wider society to reduce the impact of gangs.
Managing gangs has become an increasing focus of prisons across the country because the number of gang-affiliated prisoners has more than doubled over the past decade to about 35%, according to Corrections.
Canz national vice-president Paul Dennehy, of Dunedin, said the trend had affected Milburn prison.
While corrections officers did a great job in a challenging environment, dealing with gang members could be a very real risk to their safety, Mr Dennehy said.
"It’s a huge issue."
Correctional officers had to manage contact between some gang-affiliated prisoners while ensuring all inmates were treated legally and fairly.
Dealing with gang members in the prison environment was difficult because violence could escalate without warning.
Planned attacks on staff members, as a way to get transferred to a different prison where gang members might be planning to build a presence, was "a very real threat to our staff members’ safety," Mr Dennehy said.
Milburn was less severely affected by staffing shortages compared with other prisons and intelligence tip-offs were an important safety tool.
Prisoners could be moved around the country for several reasons and on release some decided to stay in the South.
"We’re not naive enough to think that a prisoner does their lag and they’ll be back on the straight and narrow, so if they do relocate down here there is the possibility of them bringing their criminal activities with them," Mr Dennehy said.
Former Milburn prison inmate Arthur Taylor is also aware of some prisoners, including gang members of gangs, relocating to the South after they had served their time.
"Its quite a problem, because the families usually move down, too, and bring kids. They cause trouble at the local schools and all sorts of things," Mr Taylor said.
Corrections acting national commissioner Neil Beales said it was committed to doing everything it could to ensure any person released was safely reintegrated into the community and always aimed to ensure that prisoners were in the most appropriate location for them.
"We try to accommodate prisoners in areas close to their families and when that is not possible, we try to return prisoners to their home region prior to release," Mr Beales said.
Transfers were considered on a case-by-case basis and recently some had been made to ease staffing pressure at various prisons.
Otago Corrections Facility director Dave Miller said the prison managed some of the most complex people in the country and gang violence was not something Corrections could resolve or manage alone.
Social and welfare issues, employment, education, health and mental health services and support for families and communities all needed to combine to reduce the impact of gangs.
The prison monitored new prisoners to ensure they were placed in a way that promoted safety as much as possible.
Gang factions were balanced across the prison to prevent one gang becoming dominant in any given unit.
Violence against staff was not tolerated, and monthly meetings were held to track progress against the prison’s violence and aggression strategy, Mr Miller said.
