South Australia introduced 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 each other.
Breaching the ban can be punished with up to five years in prison. Mr Goff said he was evaluating the ban, and if it worked, "then I'm 100% in favour of it".
"If it proves effective for the South Australians, then we should seriously consider introducing it here," he said.
Under the new South Australian law:
• A gang is outlawed by being declared as 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 killing of Sergeant Don Wilkinson last week is New Zealand's latest gang- and drugs-related death. The two men charged in connection with the shooting are understood to be associates of the Head Hunters gang.
Broadcaster Paul Holmes' daughter Millie faced new methamphetamine charges last week and co-accused Connor Morris is reportedly the son of a patched Head Hunters member.
Mr Goff said he spoke 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 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 former top gang detective Cam Stokes, of Auckland, who said banning gangs would just make them less visible and therefore harder to police.
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 overidden.
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's Simon Power said he was also "attracted to the notion" of oulawing gangs and would watch South Australia. The Green Party's Keith Locke said a ban would not work and would affect the freedom of association of individuals.
A Bill banning gang patches in Wanganui is before Parliament and so far 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 Wanganui. Police would be able to arrest the wearer, seize the offending items and impose a $5000 fine.
