The Independent Police Conduct Authority (IPCA) has been called in over a breath-testing checkpoint set up near a meeting in Lower Hutt promoting euthanasia.
Acting Wellington District Commander Inspector Paul Basham said in a statement he was aware of concerns around the legal basis for the checkpoint.
"It is appropriate that we notify this matter to the IPCA for its consideration," said Cmmr Insp Basham.
Last week, Fairfax claimed the checkpoint resulted in police raiding an elderly woman possessing "suicide drugs" in a nationwide operation against euthanasia group Exit International, and police have now confirmed that's true.
However, they're rebuffing suggestions they overstepped on their responsibilities, with Inspector Chris Bensemann saying they have a "duty of care" to investigate when they have "reasonable grounds to suspect that persons are being assisted in the commission of suicide".
"Police are responsible for enforcing New Zealand's laws, and currently suicide or encouraging [and] helping someone to commit suicide is illegal in New Zealand," he said.
Suicide is legal in New Zealand, though assisted suicide and euthanasia are not.
Exit International director Philip Nitschke told Newshub last week it was "well aware of [a campaign against the organisation]", but added he wasn't very happy about it.
"We understand there's been some infiltration by the police taskforce," he said.
New Zealand laws dictate it is illegal to carry out a breath test when the primary motivation for doing so isn't under the Land Transport Act, which this operation doesn't appear to be.
But police say they had carefully considered their actions before launching the operation, and they believe it was in good faith.
"We acknowledge that this is a very sensitive issue, and that there is a high level of public interest in the matter," Insp Bensemann said.
"Information gathered through the checkpoint has enabled police to provide support and information to those people who we had reason to believe may be contemplating suicide.
"The timeliness and appropriateness of this support and information was an important consideration undertaken by police in planning this operation."
ACT leader David Seymour told NZ Newswire that setting up the checkpoint was an "un-Kiwi" thing to do, and said he wants to know who was behind the operation.
"If it had come from somebody in Government, they'd have to resign immediately," he said.
"I don't personally believe in New Zealand in 2016 you've got the Minister of Police [Judith Collins] instructing the police force to go on a kind of search for people on what is a highly politically charged issue," he said.
"But you do have to wonder how the police came to get the idea that they should run an operation on this scale."
Newshub.
