More than 20 years after Sir Thomas Thorp recommended a ban on MSSA firearms, Prime Minister Jacinda Ardern says she might follow Australia's lead in doing so.
ANALYSIS: For just $25, anyone can step off a plane in New Zealand and get a firearms licence.
All they have to do is show documentation to the police, at the airport, that he or she holds a firearms licence in their country of origin.
No checks are made. The paperwork - which could easily be forged - is taken at face value.
Nor are there any checks as to why the person wants a firearm. If they say they're hunting tahr in the South Island, so be it.
This visitor's firearm licence is valid for 12 months.
They can then go into a hunting store, or online, and purchase a military style semi automatic (MSSA) rifle such as an AR-15 - the weapon of choice for mass shootings around the world. Sandy Hook, Las Vegas, San Bernadino.
And now in New Zealand.
"They pay their $25, they get a licence," former Assistant Police Commissioner Nick Perry told MPs at a select committee hearing less than two years ago.
"So I could paint a scenario where ISIS, for example, being stymied in Europe are looking for softer targets. If they did a little bit of spadework, they'd find out how easy it is to get into New Zealand, how easy it is to get a firearms licence, how easy it is to purchase high-capacity assault rifles."
The visitor's licence loophole highlighted by Perry, who was speaking as an adviser to the Police Association, was one of several examples of how easy it is for dangerous individuals to obtain weapons in New Zealand.
There's also no restriction on the amount of ammunition someone can buy, no national register of what firearms belong to which licensed owner.
Perry also told the MPs about MSSA firearms such as the AR-15, which can be purchased for as little as $2000.
An AR-15 can only be sold with a magazine holding no more than seven rounds, to comply with the conditions of the standard A-Category licence.
A 16-year-old can get an A-category licence.
You need an E-category licence, which are much harder to obtain, to buy a MSSA with high-capacity magazines.
However, Perry told the MPs that anyone - with or without a firearms licence - can simply buy larger "high-capacity" magazines online.
Some magazines can hold 15, 20, 30, 75, even 100 rounds - and slot straight into an AR-15.
MPs seized on the fact it's a criminal offence to put a high-capacity magazine into an AR-15 without the "E-Cat" licence.
In the wake of the 49 people shot and killed in Christchurch, Prime Minister Jacinda Ardern spoke of urgent reform of gun laws and made it clear she wasn't planning to tinker around the edges.
She revealed the alleged shooter, Brenton Tarrant, obtained an A-category licence in 2017 and lawfully purchased firearms the following month.
"As soon as New Zealanders hear this person was legally able to acquire those weapons and carry out this event, that will raise enormous questions with our gun laws," Ardern said.
"And that is why we will respond swiftly."
Her comments were swiftly seized on by the Police Association, which said there was no place in the upcoming debate for the radical gun lobby.
"The bitter irony with this alleged perpetrator in Christchurch is he would not have been able to buy the weapons he had in his home country of Australia," said Chris Cahill, president of the Police Association.
"Immediately after the Port Arthur massacre in 1996 the then Prime Minister John Howard acted swiftly to ban semi-automatic weapons and Australians were with him."
Thirty-five people were murdered by Martin Bryant, who was firing two MSSA firearms, in Tasmania.
Just months after taking office, Howard moved quickly to push for new laws which banned automatic and semi-automatic weapons, established a comprehensive national firearm registration, and an amnesty period for prohibited and unregistered weapons to be surrendered.
In the "buy-back" scheme, the Australian government purchased 700,000 firearms.
The attempts to reform gun laws in Australia were still controversial.
Hundreds of thousands of people protested the campaign; Howard even wore a bullet-proof vest when speaking to an angry crowd.
However, the new laws were changed and remain Howard's defining legacy.
This morning, Prime Minister Jacinda Ardern confirmed a complete ban on semi-automatics, or a "buy back" plan, were on the table.
And like Australia, such reform will be met with stiff resistance from the gun lobby in New Zealand.
Most recently, criminals getting their hands on guns was the subject of a law and order select committee inquiry in Parliament in 2017 - the hearing which Perry spoke at.
Most of the 20 recommendations were ignored by the then National government, after strong opposition from firearms lobby groups in the lead-up to the election.
But the issue of illegal firearms has been a vexed issue in New Zealand since the Aramoana massacre in 1990, where David Gray used two MSSA firearms to kill 13 people.
Police have no accurate idea of the total number of guns in the country, as records of firearms were abandoned in 1982 for a system of licensing owners.
However, a 1997 review by Sir Thomas Thorp suggested there was evidence of a substantial pool of weapons held for criminal purposes that could be between 10,000 and 25,000.
The retired judge recommended a number of changes for stricter gun control but was mostly ignored.
One of the key recommendations was identical to Australia's response to Port Arthur: to ban MSSA weapons - such as the AR-15 - and make those firearms subject to a "buy-back" scheme.
The value of MSSA weapons in hunting and target practice was limited, Thorp said.