Key Points:

Corrections Minister Phil Goff is weighing up the idea of outlawing gangs, based on a ban just introduced across the Tasman.

South Australia launched its crackdown this month with the declared aim to "get gang members to leave the gang or leave the state" by making it illegal for members to even talk to one another. Breaching the ban can lead to up to five years in prison.

Mr Goff told the Herald he was personally evaluating the ban, and if it worked, "then I'm 100 per cent in favour of it".

"If it proves effective for the South Australians, we should seriously consider introducing it here," he said.

Under the new South Australian law:

* A gang is outlawed by being declared a criminal organisation on advice from the police.

* Control orders can then be made against individual members, making it illegal for them to associate or communicate with other members and from being in certain places.

* Police can also issue public safety orders banning gangs from public places or events.

* Breaches of the law are punishable by up to five years in jail.

The murder of Sergeant Don Wilkinson last week is New Zealand's latest gang- and drug-related tragedy. The two men charged in connection with it are understood to be associates of the feared Head Hunters gang.

Broadcaster Paul Holmes' daughter Millie faced new methamphetamine charges last week and her co-accused, Connor Morris, is reportedly the son of a patched Head Hunters member.

Mr Goff said he was not surprised by the gang and drug links to Mr Wilkinson's murder.

He had spoken over the weekend to South Australian Premier Mike Rann about the Serious and Organised Crime (Control) Act, and was interested to hear that the gangs had hired South Australia's top lawyers to oppose it.

"Why would they oppose it so bitterly if they didn't think it was going to be effective?"

Mr Goff's position differs from previous comments by Police Minister Annette King, who told Parliament in March 2006 and November last year that she did not not believe it was "feasible or possible" and to think it would actually work was "dreaming". Ms King is also following developments in South Australia.

Mr Goff said the ban had to be assessed, because while it might be popular with the public, "it is not what looks good, it is what actually has a significant impact on gangs".

Mr Goff cited the recent comments of Cam Stokes, Auckland's former top gang detective, who said banning gangs would just make them less visible and therefore harder to police.

Mr Goff said: "You can pass a law banning gangs, but has that ever stopped the Mafia, Yakuza or Triads from operating?"

South Australia has a Labor Government and Mr Goff and Mr Rann, a former NZ journalist, are close friends.

The South Australia ban has been criticised for limiting freedom of association, but Mr Goff said he agreed with Mr Rann that the gang problem was serious enough for civil liberties to be overridden.

NZ First's law and order spokesman, Ron Mark, said the party had long advocated banning gangs and he welcomed Mr Goff's "change of attitude", given previous criticism by Labour. "We are a little cynical given we are so close to an election and they have consistently rejected our calls to outlaw gangs."

National Party spokesman Simon Power said he was also "attracted to the notion" of outlawing gangs.

Green MP Keith Locke said a ban would put a barrier in the way of working with gangs to stop their criminality.

A bill banning gang patches in Wanganui is before Parliament and has the support of all parties except the Greens, Maori and Act.

If passed, the Wanganui District Council (Prohibition of Gang Insignia) Bill would ban patches and even gang colours or tattoos in the city.

Changing their tune:

"To say that if we outlaw [gangs] by law, that will happen, is, I think, dreaming."
- Police Minister Annette King, March 16, 2006

"If it works, then I'm 100 per cent in favour of it."
- Corrections Minister Phil Goff, yesterday