Police Commissioner Andrew Coster is asking for greater clarity from New Zealanders about what they see as acceptable intelligence gathering by police.
He said this week the police had been criticised both for undertaking routine intelligence collection and for failing to undertake routine intelligence collection.
"Is it just me, or are we having trouble making up our minds about what we want?" he said in an opinion piece in today's Herald.
He said he wanted a balanced public conversation about it.
He said he was not pushing for greater police powers but there should be debate about what the boundaries should be and what trade-offs were involved, he said in an interview yesterday about his op-ed.
Police were criticised for alleged failure to scan for threats related to a bomb threat made against Christchurch mosques.
Police were also criticised for collecting information – in some cases photographs – from young people in various centres in New Zealand and recording that information for possible future use.
The issue of taking photos is the subject of inquiries by the Privacy Commissioner and the Independent Police Conduct Authority.
"But it's not in the end just about photos," Coster said.
One of the stories this week for which drew criticism was about police speaking to a group of young people and recording information about what they were doing and who was in the group.
He said that information might have been in an area where young people had been involved in burglaries and ultimately it might have helped prevent further burglaries.
"The downside of it is potentially those young people were actually not doing anything wrong and police speaking to them left them feeling targeted, left them feeling like they were being treated the wrong way, relative to what they were up to."
Part of the issue was how they were spoken to.
"But in the end, the process of trying to prevent crime and make communities safe isn't an absolute science.
"You can't surgically only engage with the people who happen to be committing an offence because most of the time, you are not really sure until you have secured evidence and you have to engage in order to secure evidence."
Generally people would expect police to be on the lookout for risks to safety.
"But the consequences of us being on the lookout can be that we end up speaking to people who were actually doing nothing wrong.
"These are the kind of things we grapple with and we say 'how should we be encouraging our people to engage when it comes to prevention? What are appropriate triggers for police to go and have a conversation with a group of young people? When would it be appropriate for us to gather their details as opposed to not doing that and simply sending them on their way."
The questions were not for the police to answer but for the community.
Relative to the population, police were small in numbers "and we rely on the vast majority of the population to buy in to what we do and how we do it because without their support and without that sense of legitimacy, we can't actually operate."
Different countries had different settings, and different populations had different appetites for how far police should go.
"I just think that is a really healthy conversation to have."
He is planning to announce a new panel today that will give the police advice on the use of new technology, especially emerging technology, including CCTV and the ethics of how it should be used.
On the issue of police taking photos, Coster said the policy was clear.
"Unless there is a legislative provision for the photo to be taken which relates normally to someone for an offence or unless we have the informed consent of the young person and their parents, then we shouldn't be taking photos.
"There may just be examples here from the thousands of interactions that we have where we have got it wrong and if we have got it wrong we will deal with it. We need to be really clear about that.
"Those are quite fine judgments and sometimes the conversation around those activities ends up casting that police activity in a particular light which may or may not be a fair reflection of the motivation of the officers involved."