National leader Bill English says his deputy, Paula Bennett, did not describe their policy in the right way when she suggested serious criminals should have fewer human rights.
Watch Bill English's interview with Morning Report's Susie Ferguson:
The party is pledging to give police the power to search cars and houses of the most serious criminal gang members for firearms at any time, if re-elected.
The plan has been criticised as "troubling" and sinister" by one expert on New Zealand's gangs.
National would also spend $82 million over four years on measures to curb the sale and supply of methamphetamine, with a particular focus on gangs and drug dealers, and on funding more drug addiction treatment including 1500 additional in-patient places.
Mrs Bennett, when discussing the policy yesterday, said the measures were necessary to reduce the harm caused by some gang members.
"We just feel that there are some gang members that are creating more harm and are continuing to create harm ... They have illegal firearms, police have a really good reason to suspect they have, and on that basis they are going to search," she said.
"Some have fewer human rights than others when they are creating a string of victims behind them."
But Mr English told Morning Report Mrs Bennett had misused the term human rights.
"It's just not the right way to describe human rights," he said.
"She understands the policy the right way, but it was a discussion about the legal rights of particular people, not the human rights of New Zealanders.
"Sometimes we just don't say the right thing, that happens."
Mr English was standing beside Mrs Bennett when she made the announcement yesterday. He did not pull her up on the error at the time because he dealt with his colleagues civilly and in an appropriate manner, he said.
"It wasn't a matter of being happy to let it go," he said.
"I described it myself in terms that were more correct, that were correct, and the policy itself is actually very important, because methamphetamine is a problem across our community.
"It needs to be dealt with and we are putting in front of the public a range of tools [that] will assist us to deal with it, and there's no doubt at all that the gangs are at the centre of the distribution system."
'It's shaping up as a tight race between National and Labour'
Regarding the upcoming election and recent polling, which showed the two main parties on almost equal footing, Mr English said he thought Labour leader Jacinda Ardern's momentum had now stopped.
"I think people are now considering the choices because they can see there is actually the possibility the government could change, they haven't thought of that for quite a long time."
He thought the contest would be good for the party, he said.
"It's shaping up as a tight race between National and Labour, and now that people realise that, they're starting to look at the policy and what difference it will actually make in their households and their businesses, and I think we will benefit from that.
"And they're thinking about their choices around the economy - can we take economic management for granted, and around the spending.
"They look at the opposition, it's a bit of fairly vague confused policy that appears to take the economy for granted, as if the golden goose will just keep laying, they don't need to pay it any more attention than just pull a few more eggs out of it."