"Other police Facebook pages also contain a lot of community and crime prevention information," says Commander Paterson. "We didn't want to make ours too cluttered. Most of our material on the page is from security footage where we want to identify a criminal in action who is often not someone known to our own staff.
"We've had three big successes so far and all matters are still before the courts. One was an alleged aggravated robbery, another was a serious handbag snatching incident and the third was an arrest for $20,000 of stolen jewellery. The owner didn't even know she'd been a victim but saw her gold bracelets on our page, checked and found they were missing from her house."
He said the Facebook page can be time consuming to keep up-to-date - images need blurring once arrests are made, for example - but Paterson says it's an ideal way to engage with people, particularly the under 35 age group.
"The fact is if you're under 35 you tend to be a 'Facebooker' and if you're over 40 you angle towards being a 'Googler'. We can't miss out on that huge under 35 audience. We have to be where they are, use their language and communication style."
He says under 35s' level of engagement online almost sees the virtual and real worlds become one. Their internet browsing is largely done from the Facebook environment, so the police presence there is important.
Posting pictures asking for people to identify offenders can lead to some users thinking it's hilarious to suggest the name of friends - or enemies - as the criminal.
Paterson says it's not too common. "I think people realise that dealing with the cops is something to be treated seriously," he says.
It's also unlikely anyone could be defamed by being falsely named as a potential suspect, in his view.
"There would be some explaining to do and we'd treat each case on the 'intent' and any harm that was actually done," Paterson says. "A malicious lie about an identity would be uncovered pretty quickly and even though information sent to us by email comes through secure indirect links, almost everything can be traced in the cyberworld if we really had to."
As for any objectionable comments, police are applying common sense in keeping with the social media forum being used.
"We control the feedback but are open minded enough to allow negative comments to be viewed. We just keep out the inappropriate or really crazy stuff."
He said there are several dozen ad-hoc police Facebook pages up and running around New Zealand. In the Waitemata Police District, police will shortly be bringing all four of theirs under a single site where viewers can just click the link they want.
Read about the Beach Haven Police Facebook page.
Others include the McLaren Park Neighbourhood Policing Team
Link to other police Facebook sites here