When the alarm went, it fell to the STG team. The message to activate was relayed by an inspector and the small group of men raced the 50m from the cottage to the foyer of Government House.

“We get to a back door, quietly went in and took up position around the foyer. [Then] the stack is going upstairs.”

A stack in this context is a line of operators – the elite specialists who train for extreme situations – moving in concert, preparing to execute a pre-trained sequence of tactics and techniques.

“We were met by one of the staff who showed us her rooms. We were on our way there, it was going through my head about what sort of tactics we should employ.

“Could be unannounced forced entry or an announced entry where we knock on the door and see what we’re presented with.”

Edge doesn’t have the liberty of time. One of the world’s most famous people – and New Zealand’s head of state, Queen Elizabeth II, in New Zealand for the Commonwealth Heads of Government Meeting in 1995 – could be facing a serious threat.

As he says: “This is the good Queen Elizabeth the Second.” Handled poorly, the ramifications are almost unimaginable.

“Doing a building entry in any scenario is highly dangerous if there is an offender in there. First one to go through the door – and the second – it’s highly possible one is going to be shot, which is going to upset the dynamics of the team.”

At that point, Edge could see another way forward.

“So, I decided to call the butler along to do the door knock.”

The butler approached the door, the STG stack to either side ready to explode into action. As Edge prepared to go, the door opened and the butler asked if she was okay, telling her the alarm had sounded.

“Yes, I’m fine,” Edge recalled the Queen saying in her cut-glass tone with no sign of stress.

The Queen gave no inkling she was aware there were armed men stacked along the hallway. It’s likely she never knew.

The butler withdrew, the door closed and the STG team quietly returned to the cottage.

‘Last line of defence’

That story and a career’s worth of others are told in Edge’s book, Last Line of Defence. He even has another royal revelation from the barbecue former Prime Minister Sir John Key hosted for Prince William.

The book is a collection of Edge’s experiences over a lifetime of policing, most spent in the STG.

In crafting those stories, he has revealed the hidden role of the elite unit in major police operations

Edge, now 67, spent 37 years with police, with much of it as a member of the elite Special Tactics Group.

It was a career interrupted with a rewarding break working in Papua New Guinea, initially providing security for the Australian High Commission and then for a larger, private-sector security company. After retirement in 2014, Edge returned to the country as operations manager for a helicopter company.

Edge’s pathway to police began straight out of high school when he was told to come back after a year of work. “Why don’t you come back when you start shaving,” he was told.

He did, signing up aged 19 in January 1977, and initially – after training – working general duties in Dunedin. That led to the Armed Offenders Squad and becoming a police dog handler. As a dog handler, Edge also filled an essential AOS role until his dog, Lance, was killed on duty in October 1991.

From there, Edge went into the police undercover programme and writes in the book of the positive and less-positive elements of the fledgling programme it was in the 1990s. Edge’s recall included the “drug avoidance training” during which officers were sequestered away with cannabis, learning how to roll it, smoke it and cope with being stoned.

“I quite liked it,” he said in the book. “I’m pretty chilled at the best of times.”

Edge’s career didn’t lead to undercover work. Instead, he returned to a familiar pathway and joined the Special Tactics Group.

His entry into the Christchurch unit – one of three across the country – came after years of AOS work and coincided with the departure of the incumbent sniper. As a result, Edge took up the marksman’s role.

For Edge, it was a trade to learn and perfect. He had shot possums and rabbits as a younger man, but hadn’t used heavier-calibre weapons or fired at range.

Callouts were often to domestics. Police have a range of resources – usually, a police negotiator would be speaking to those he or others might be forced to shoot – and Edge, with his rifle against shoulder and eye down the scope, was the last resort.

“We’re there to save the victim. The offender comes second. You’ve just got to prepare yourself to have a shot if you think the victim is in imminent danger of death.”

Asked about that point of tension, Edge plays it down. It is, he says, the same possibility frontline police deal with daily.

“Having said that, it’s a different mindset with the sniper. We train for it just about every day. It’s what we’re there to do.

“The poor copper on the front line, they’re only doing limited training throughout the year. There’s a lot more pressure on them if they draw a firearm. I’m already prepared for what’s going to happen.

“I’ve had dozens and dozens lined up. You’ve got your finger on the trigger. You’re almost waiting for the moment where the offender is going to carry out an action that’s going to make me think, ‘this is it, I’m not prepared to put the victim’s life on the line any further. Next time he does this, whether it’s a firearm or a knife, I’m going to shoot’.

“There’s no doubt in my mind I’m going to pull the trigger.”

When asked if he had done so over the years, he says that’s not something discussed by those forced to fire. It’s the job they’re there to do, but it’s not a part of the job those involved talk about.

“We don’t sit down and think about it too much … about what we’re being called out to do.”

For all Edge’s early years policing in Dunedin, he wasn’t there when David Gray’s rampage killed 13 people, including Sergeant Stewart Guthrie, one of the first officers to turn up in response to reports of a shooting.

A day earlier, he had left Dunedin to do the sergeants course at the Royal New Zealand Police College.

“I have no doubt I would have been standing beside Stu Guthrie. It’s always annoyed me that I wasn’t there, although the guys who were there said it was better off I wasn’t.”

Despite that advice, Edge said: “You have in your mind you might have been able to help, that it might have had a different outcome.”

‘Not here for tiddlywinks’

The STG evolved out of New Zealand’s move in the 1970s to recognise the growth in international terrorism. In New Zealand, there were two responses – the development of a counter-terrorist capability in the NZ Special Air Service and a similar one in the police.

Edge writes in the book that the STG’s core job is counter-terrorism and, after that, “they are kicking down the doors of New Zealand’s worst criminals”.

“When the patrol cars arrive at a job and can’t resolve the situation, they call the Armed Offenders Squad, and if the Armed Offenders Squad arrives and can’t resolve the situation, they call the Special Tactics Group.

“They are New Zealand’s last line of defence. If STG turns up on your doorstep, God help you. They haven’t come to play tiddlywinks.”

As Edge explains, reaching the level at which police in the STG need to operate requires intense focus and preparation.

“The mindset hasn’t changed from the 1970s. The focus is train, train, train for a terrorist attack.”

That includes developing specialist tactics, including for arrests, building entries, surveillance and other skills.

“The gangs really can be looked on as urban terrorists. The way they carry on, shoot at each other, defending their territory. They’re pretty much treated as that.”

Today’s New Zealand is one in which police face many more firearms incidents when called for help. South Island cities and towns, back when Edge joined the STG, saw much-less immediate threat of violence.

Also, back then it was cut-down .22 rifles or shotguns. “There weren’t the semi-automatics there are now.”

On the post-March 15 ban on automatic weapons, Edge is blunt. “That was a great thing. It had to be done. That legislation was a long time coming.

“But it hasn’t taken the pressure off as such. [These weapons] are still out there and still getting into the hands of gangs.”

“The criminals out there have just got more dangerous. The meth is huge as far as gangs go,” he says. With higher stakes come higher risks.

It has had the STG evolve to its position of carrying out high-risk arrests and doorknocks regularly. That, too, is under evolution, with police tactically targeting those facing arrest away from places that might lead to a stand-off or worse.

“They follow them somewhere – to a supermarket, petrol station – and do a quiet arrest in the carpark or forecourt. They’ve even done it the odd time with someone sitting in a vehicle at traffic lights in Auckland.

“It makes those guys paranoid. They don’t know what’s coming.”

In the book, Edge has described a string of operations during his years in police, but particularly with the STG, that reveal the elite unit’s role in major operations.

Among those is Edge’s recounting of one of the biggest marijuana busts in New Zealand’s history that took place in 1996-97 in the Whanganui National Park bush.

He tells of four STG snipers being airlifted into the bush and then hiking days with heavy kit to reach an observation point

The reconnaissance mission was followed by a planned raid that drew 15 STG operators from Auckland, Wellington and Christchurch to the bush. Edge recalls being dropped at the same place as the initial recon snipers and hiking for days.

At the cannabis-growing base, those camped and cultivating the 4800 mature plants police would seize had no idea their bush hideaway was surrounded by a heavily armed police unit of highly skilled assaulters.

“Shock and awe” and visual intimidation in a dawn raid were the keys to that day’s quick arrests, Edge said. Only seconds after police emerged, the surprised growers were face down in handcuffs alongside the semi-automatic AK47-style rifles and handguns they had kept several.

It was one of several missions described by Edge that took STG members into the wilds of New Zealand, hidden and silent teams of armed specialists wrangling their way through some of our toughest countryside.

The risks encountered are, at times, unexpected. Edge writes of the danger of boobytraps around cannabis plantations, from trip wires attached to shotguns to punji stakes and fish hooks smeared with cyanide.

Such was the risk, STG members expanded their high-level first aid capabilities to incorporate the administration of a cyanide antidote.

If anything, Edge gives the convincing impression that STG members could be lying in wait anywhere at any time. He writes of one surveillance job in which the armed target was “five paces in front of me”, unwitting as to his imminent arrest or the police officer right in front of him gathering evidence.

A close royal call

It wasn’t all bush bashing and camouflage. Edge details protection and security arrangements for a cluster of VIPs, including former US President Bill Clinton, US Secretaries of State Hilary Clinton and Condoleezza Rice, Fifa’s Franz Beckenbauer and, of course, the royals.

Alongside Edge’s story of nearly bursting in on Queen Elizabeth was another involving her grandson, Prince William, attending Premier House in 2010, when he and then-Prime Minister John Key hosted a barbecue.

Edge was in charge of planning security for the visit and for which he had received clear instructions, via the Visits and Ceremonial Office, from key: “I don’t want Premier House looking like Fort Knox.”

There were no specific threats aimed at William, or major protests, and that gave Edge leeway in the scale of security required. It allowed a relatively low-key security presence with STG snipers hidden in the bush at one end of the property.

As Edge writes, it almost went horribly wrong because of a radio station stunt. That in itself made headlines, but could have made many more.

A 19-year-old working for the station tried to blag his way in through the front gates, and then jumped a fence further down the road, making his way through properties until he was wandering into Premier House gardens from a direction where no one should be approaching.

Edge said in situations such as this, STG snipers could have been lying in wait for hours and then – suddenly – they are confronted by an unexpected, unannounced individual who is clearly not meant to be present.

“Looking back, most people would look on it as a bit of a laugh. But there are unseen consequences that could have a bad outcome.

“It could have been a lone-wolf situation. Sometimes the public thinks terrorists look like big green monsters.

“But usually lone wolves are insignificant individuals that just appear – could have had a knife or a firearm.”

Edge said his emergence would mean “your heart starts pounding, adrenaline starts pumping”. “Who’s this guy? He’s not meant to be there.

“There’s a lot on your shoulders. You’ve just got to fall back on your training.”

As Edge describes the scene, it underscores the STG’s relative autonomy of action in a tactical situation.

“It’s solely on you to decide when you pull the trigger. Things become very clear in your mind very quickly.”

In this instance, it passed without incident. The teen was intercepted before he could approach the VIPs.

It could have gone a different way, he wrote. If the young man had got past DPS and William’s protection officers, he would have been “in extreme jeopardy” as a “genuine threat”.

Although the protection officers have seconds to draw a holstered weapon while assessing a situation, the snipers “were tracking the prankster with their fingers already on the trigger”.

On this day, like others, that finger tensed to fire then relaxed with no shot fired.

Edge closes the book with an account of the threats faced by New Zealand.

“Terrorism in New Zealand won’t go away,” he writes, referencing foreign interference by China and Russia and online radicalisation, particularly among young people.

Each of those issues has solutions that – hopefully – emerge long before shots are fired and lives are lost.

But if it does come to that, Edge says New Zealand is well-served by the STG. Specialist teams visiting New Zealand for training reflect a high regard for its capabilities, he says.

“We have one of the best tactical units of its type in the world. We don’t like to blow our own trumpet but we see how we’re doing on a world stage.

“Our level of competency against those overseas operators come to train with us and we can take a cue of what we’re doing. We can be confident – and New Zealand can be confident.”

David Fisher is based in Northland and has worked as a journalist for more than 30 years, winning multiple journalism awards including being twice named Reporter of the Year and being selected as one of a small number of Wolfson Press Fellows to Wolfson College, Cambridge. He joined the Herald in 2004.

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