Kiwi-born criminals deported from Australia are contributing to a professionalisation of New Zealand gangs, which is likely to lead to a spike in drug-related violence according to the new Police Association President.

Chris Cahill, who's been in the job since October, says methamphetamine is the biggest driver of crime in 11 of the 12 police districts.

Trade in the drug has turned gangs into a multi-million dollar industry, which is getting worse with the arrival of the deportees from Australia.

"We're getting some key Australian gang figures from big gangs like the Comancheros and Bandidos.


"They're able to add a level of professionalisation to those gangs that we haven't seen before."

Police figures show 660 New Zealand passport-holders were removed from Australia between January 1, 2015 and January 19, 2017.

It's expected around 840 more are on their way.

Cahill says many of the new arrivals are joining gangs that deal in methamphetamine, increasing competition and in the process, the risk of violence.

"With any business there's competition around your market.

"With gangs the way they deal with competition is to start fighting. In Australia we've seen some significant gang violence, shootings, murders.

"The risk is the new arrivals could bring that level of violence here."

Cahill says the police and government have recognised the problem and are acting.


"We're not putting our heads in the sand. We have 80 more organised crime staff and they are doing everything to deal with the problem before it gets out of control.

"When you understand the issue, you've got a much better chance of dealing with it.
But the gangs are well established and there's a lot of money involved.

"It isn't going to be easy and it's going to take a lot of hard work."