The ACT Party is accusing the Government of failing to provide police with enough power to take firearm licences off gang members.
The number of people identified on the national gang list who hold a firearms licence sits at 12.
A law change in December gave police more power to revoke firearms licences on gang affiliation grounds.
Police Commissioner Andrew Coster says the recent changes around gang affiliation and the fit and proper person test is of "uncertain effect".
"We think it is unlikely that gang membership by itself will be sufficient to remove somebody's licence but we intend to test it," he said.
Coster said this issue was well traversed during the select committee stage, before the law change.
"It sits uncomfortably with us that gang members have access to firearms, but we also need to recognise that some of the people who have licences on that list have had them for decades and some of them have no convictions and these are difficult judgements to make," he said.
ACT MP Nicole McKee said this was deeply disappointing.
"Especially when Government have stood up in the house and said the reason why they put through rushed legislation in the first place was to take firearms away from gangs," she said.
McKee said it showed rushed legislation did not get the desired result of keeping the country safe, and she argued that being a gang member alone should be enough to have their licence revoked.
"If you are on that national gang list, you are on that list for a reason and we've got the New Zealand Police saying the people on that list, who they have concerns about, are able to purchase firearms legally," she said.
Police Minister Poto Williams said it was simply too early to know how these provisions would be applied before being tested in court.
"They are a tool for police so that those on the national gang list can have their firearms licence removed if the police believe they are not a fit and proper person and associated with a gang," she said.
Williams said these provisions were designed to keep New Zealanders safe, and National and ACT had voted against them.