Key Points:

We're some way into a long interview, and Howard Broad interrupts me mid-question.

"Can I just make a point," he says, rather than asks. "We are not the police force. We are the New Zealand Police. We got rid of being the police force in 1958, and we got rid of it for a reason, and that's because we are a public service and we, well I in particular, don't like being characterised as a force. We have the power to use coercive power when we need to, but our primary strategy is to use our influence and our persuasion to stop people.

"And I know I'm probably the only person who still makes the point," he laughs. "It's been 50 years now."

I apologise.

"That's all right, you're amongst some pretty big company."

I have just been corrected by the Commissioner of Police, and somehow I feel less told off, more enlightened - which says something about his leadership style.

Forget any ideas you may have of command-and-control, process-driven, hierarchical management. Our top police officer could, among the unsympathetic, be described as having a touchy-feely style. But if it works on his troops half as well as it works on journalists, he'd have to be one of the country's more effective leaders.

"Early on in my career when I was a bit less wise, a bit dumber," he says self-deprecatingly, "I thought that you could offer criticism, and that you could point out faults, and that people would see that as a logical thing to change and be motivated to change. But I've realised over my career that humans generally aren't like that, they're attracted to the warmth of the limelight, and you've got to find ways to show people where it's good to be, rather than point out where it's not good to be.

"You never criticise people to success, you encourage people, and you find opportunities to shine the light on someone else."

He's come a long way - personally and professionally - since signing up as a police cadet just shy of 18. The motivation to join the police wasn't, he admits, all that well thought out.

"The expectation of the family was that I'd go on to university and, in fact, only my oldest brother and I from among the whole bunch of cousins didn't do that immediately [he has since gained a law degree].

"I sort of felt like I wasn't quite going to satisfy expectations. I guess I was a bit worried about that."

But the police would involve him with the law, the job had an element of public service, and the young Broad could not only continue with his competitive sport, but it would be encouraged (he has represented the NZ Police in both soccer and cricket).

He thought he'd give it a go.

"I did actually quite like being a street officer. People always find when they get into the police it's a lot wider and more diverse than what, possibly, you might think when you consider it as a career.

"It's not all about Starsky and Hutch and it's not all about Highway Patrol.

"There's a lot of human interaction, there's a lot of study required to keep up with the play with what the law is, what the sociology is with handling these interactions."

After two years as a beat cop, he joined the CIB - and gained a motivation for studying that hadn't been there before.

"I think at school I was struggling a bit, I didn't really know what I was studying for, and then when I got into studying for the detective [exams] it was very clear why I was doing that.

"When I was on the street as a uniformed cop, I hated getting into a situation where I didn't know the law, [if] I didn't know the practice associated with something. So if I did get into that, I found that I would always go away and swot up so that it would never happen to me again."

Somewhere along the way Broad's motivation changed. No longer was promotion the main goal, and no longer was studying just enough to pass the exams. He he wanted to know as much as he could.

"I developed within the police, rather than before I joined, this sense that the police was really an incredibly important organisation and the people within it do an incredibly important public service.

"Having a slightly reforming dimension to my character, that sort of took over when I got into my 30s and I got exposed to a lot more of the philosophies of policing and exposed to the potential that police as an organisation were not just people who, you know, lock people up, but people who can help a community and a society."

The 1980s saw a big emphasis on community policing, and on leadership within the entire public service. Broad was in his element.

He's been less in his element over the past two years, during which, I suggest, he's had a bit of practice in crisis management. He admits it's been hard. Indeed, when asked to name the low point of his career, this is what he volunteers: "I guess it would have to be the fact that I take public responsibility for things that have gone on in the police in the course of my career but for which I'm not personally responsible, and while I would be quite comfortable with that, the way that sometimes it's conveyed, is intensely personal.

"When I look around at the thousands of good men and women in the police and I see how much that hurts, it's the same feeling, I'm sure, that I've got. That's probably the low point."

We both know exactly what he's talking about.

But despite everything, he reckons the public still hold the police in high regard - and that rubs off on him.

Then there are the police themselves. The sincerity - and bursting pride - as he talks about the people he leads is not something often heard.

"I'm beside myself, really, in terms of how well the people in the police treat me. Like, I'm the person who allocates where the resources go, and the person who represents them on the telly at night and in the papers, and so often you're constrained in what you can say - I know what they want me to say but there's obviously legal or some other reasons why you've just got to hold fire.

"And these people just provide me with so much support and they encourage me. I sit there saying, 'Well I'm supposed to be encouraging you', and these people are weighing in behind me. That's hugely uplifting, and that provides more than sufficient counterbalance to some of the dark bits."

Broad's under no illusions that the events leading to last year's Commission of Inquiry into Police Conduct dented public faith in the police, and that things have to change. For a start, he says, the old-style disciplinary process that kicks in when someone oversteps the line "has made us look a bit stupid in some senses". But that's changing. And the dominant leadership style has been evolving and continues to do so.

"I'm more about influencing people to want to do the right thing as opposed to command and control, 'You've got to do what I say because I've got the most badges of rank on'.

"That produces some interesting little conflicts because here am I saying I really want people to step up to do the right thing because they want to, they can do and if every time they do something that is not quite right and I jump in over the top of them simply to sort things out, or fire someone simply because they've made a mistake, that's quite counterproductive to the sort of culture that we need to build in the police.

"We need all 11,000 people stepping up to deliver what every John and Jane member of the public wants them to so there's a bit of a conflict there, a bit of a risk really."

The risk is being managed by providing training and mentoring not only to young officers seeking promotion, but also - perhaps especially - to older officers used to a different culture.

Broad's contract as commissioner runs for five years - he's got three to go. Tough as it may be, he's adamant he enjoys it. "The satisfying parts of it are just so buzzy. Some days you get home and you wonder if you've been run over by a truck and you wonder if you're going to be able to climb off the floor. I find that the things that are really hard are around my own expectation of what I can do or whether I've possibly let someone down. Those are the things that are most difficult to deal with.

"I've found that I can soak up a considerable amount of pressure on behalf of the police.

"In some ways I can compartmentalise the fact that I'm Commissioner of Police. I'm only the Commissioner of Police for a short time. So long as I can look myself in the mirror when I get up, I can continue to do that job."