The National Party is reviving its call for the government to drop its target of reducing the prison population by 30 percent.
It comes in the wake of Thursday's deadly shooting at an Auckland construction site.
The gunman, 24-year-old Matu Reid, had been serving a five-month home detention sentence for family violence crimes.
The Labour government in 2018 promised to reduce the prison population by 30 percent within 15 years.
National's Paul Goldsmith said that target, combined with no restrictions on judges' ability to reduce sentences, had weakened the consequences offenders face.
"Downgrading prison sentences to home detention poses clear threats to community safety which Labour continually refuses to acknowledge.
"Home detention rarely means offenders are confined to their homes, with many attending workplaces and other public places. Home detention has its place, but ultimately, an ankle bracelet only tells authorities where someone is. It cannot stop them from harming innocent New Zealanders," Goldsmith said.
Police Minister Ginny Anderson told Morning Report it was too soon to say if the gunman should have been in jail.
"We need to know first what went wrong, before we can start saying how we would want to fix the system. Those decisions in terms of whether it's home detention, those are all factors taken into account through the court system and through the judiciary, and they weigh up the individual circumstances of the person concerned."
As well as the police's investigation, Corrections has launched an inquiry into its management of the gunman.
Prime Minister Chris Hipkins has also asked for advice on whether a wider review is needed.