New gang laws coming into effect from midnight are part of a broader effort to make life more difficult for gang members, Justice Minister Paul Goldsmith says.
But it will be impossible to know what impact the changes will have on the reduction of victimisation, he says.
Under the new laws, gang insignia will be banned in public places, police will be able to break up large groups in public "if they are causing fear and intimidating" and police could issue non-consorting orders to stop gang members from associating or communicating for up to three years.
Being a member of a gang will also become an aggravating factor in sentencing.
When asked when he thought there would be a reduction in crime statistics as a result and how it would be tested the laws have made a difference, Goldsmith told Morning Report the changes were part of a broader target to reduce the number of serious victims of crime by 20,000 by 2029.
"The issue of course is that crime as we know is very complex and so it's impossible to identify what this one element of a broad plan is having on the over all effect [on victimisation numbers]."
But a continued reduction in crime would show they were effective, he said.
It would be important to deal with some of the longterm drivers of crime, Goldsmith said.
The government's truancy efforts and goal to reduce the number of kids growing up in emergency accommodation were a ways to tackle youth crime, he said.
"You've got to do 20 things consistently (to tackle crime) and when you've made progress on them, start on a new bunch and that's what we're doing."
Gang members were a very small subsection of society at less than a quarter of 1 percent of adults but responsible for a significant amount of violent crime including about 20 percent of homicides, Goldsmith said.
"So we're not going to make progress on our fundamental goal, which is to reduce the number of victims of violent crime in our society, without being more effective in tackling the gangs."
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