A lack of understanding of gangs results in policy that is "always going to get it wrong", sociologist Jarrod Gilbert says.
It comes as an increase of violence and gang numbers has spurred promises to crack down on gangs. However, these pledges are not new and comes from both sides of the House, Dr Gilbert said on TVNZ1's Q+A.
"We use this term 'gang' to define the Mongrel Mob, a large predominately Māori gang, we use it to describe these elite outlaw motorcycle clubs like the Hell's Angels, we use it to describe young people with bandannas, we call this all gangs.
"We have policies that target this word gangs, yet we don't see similarities in the scene, we see difference.
"Even these most elementary understanding of our scene aren't accepted by politicians and many in the public, therefore when you're devising policy you're always going to get it wrong," Dr Gilbert said.
"The gangs sound great on the hustings, but they are far from our greatest concern around crime and justice issues in New Zealand. This is something far biggest in law and order."
Dr Gilbert said the most recent increase began in 2008.
"The numbers have increased an the inevitable consequence of that is some gang violence. It's not new by any stretch, but it feels new because we haven't seen it in a long time."
"What happened in 2008 was that there was a resurgence of young people joining, and what we've seen is the growth come from that.
"The people coming back from Australia have had some impact, but more than that it's when the Rebels (Australian motorcycle gang) came here in 2008... what they demonstrated by patching up a lot of people very quickly is that the appetite and the scene is still there and other groups tend to respond."
He added social media, methamphetamine and surges of popularity also influenced gang numbers.