Christopher Luxon says the approach to crime needs "not just carrots" but also "sticks".
It comes as the National leader this morning rejected a new report into gangs in New Zealand by the Prime Minister's chief science advisor Juliet Gerrard.
The report said reducing gang harm required tackling underlying socio-economic issues, including inequity, intergenerational trauma, housing and family violence.
It also said evidence suggested "scared-straight" or "boot camp approaches" were ineffective, and "a zero-tolerance style of policing builds distrust... it creates alienation and dislocation from communities and risks fuelling gang membership".
At Waikato University today, Luxon said a National Government would work on the causes of crime "through Bill English's thinking, called social investment".
The PM's team of top experts have come up with an alternative plan to tackle gangs. (Source: 1News)
"That's a big priority for us, we’re going to work on those long-term challenges and that social deprivation that often is a driver and leads into a life of crime.
"But at the same time, you've got to be able to have not just carrots, you also have to have sticks.
"The message from this soft-on-crime Government has been this is permissible activity.
"Gangs are not nice people. They want all the rights of being Kiwis but they're not prepared to take the responsibilities of being Kiwis. They peddle in misery.
"We are going to be tough on gangs."
That included policies to ban gang patches in public places, giving police special powers to break up gangs in public places and making gang membership an aggravating factor in sentencing, he said.
He said National's policy was evidence-based, not reactionary, and he planned to "go through and read [the report] properly".
ACT justice spokeswoman Nicole McKee did not accept the report's contention that colonisation played a role in gang membership.

"[The] report on gangs blames colonisation, crime against gang members, and the idea that society has rejected them.
"The process of colonisation ended in the late 1800s. Yet according to this report gangs didn't start emerging until the 1950s. Why the huge time lag? If the two are linked, gangs should have appeared much earlier. It's just another excuse for bad behaviour.
"Elsewhere, the report labels gang members victims of crime and says they've been rejected by society. There's no call for gangs to take responsibility for the fact they're terrorising communities.
"The report attempts to claim that if only the authorities are nice to gangs and treat them as friends, they'll start being nice back. But Labour has subjected New Zealanders to a real-world experiment and gangs don't improve their behaviour; in fact they get worse.
"Massive changes in education, welfare, and the economy are required. The education system doesn't educate people, the welfare system rewards idleness, the economy isn't producing enough jobs or high enough wages, and the justice system isn't arresting enough gang members. It's no wonder people are attracted to gangs under those conditions."
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