New Zealand Prime Minster Ardern said the main gunman used five weapons, including two semi-automatic weapons, two shotguns, and a lever action firearm. She said he held a category A firearms license and appeared to have acquired his weapons legally. The licence was obtained in November 2017 and the gunman began purchasing the weapons in December of that year.

Despite the recommendation of the select committee in 2017, a Category A firearms license currently allows the ownership of some semi automatic weapons. The difference between “Military-Style Semi-Automatic” (which are included in E Cat and “Semi-Automatic” weapons (which are Category A) is largely cosmetic, but still have similar capacities.

One of the pivotal points in the legality of these rifles was the court action loss by the police in Police V Lincoln in 2010, which allows a so-called “thumbhole grip” to be exempt from the definition of “free standing pistol grip”. The end result is that weapons which can be easily modified to take high capacity magazines are complaint and can be passed as Category A if they are fitted with only a 7-round magazine.

So one of these is “thumbhole stock” and one is not, yet it’s technically the same rifle.

This means with a Category A license you can go and buy a gun with a “thumbhole” stock (loosely defined) and it is legal until the moment you put an 8- (or 20, or 30) round magazine in it.

Nearly all AR-pattern rifles, the rifles famous for mass shootings in NZ, are A-Category compliant by default, because the legislation to correct the technical distinction has not changed. This matters because these weapons should be in E Class, a vastly higher level of restriction, with more vetting, stringent gun storage requirements, and other restrictions on use and purchase, such as serial number registration.

But due to the thumbhole stock loophole, you can get 90% of the functionality of an MSSA on an A-Category license, soley due to the cosmetic differences from the technical definition of a “military Style” weapon.

The adoption of the 2017 select committee recommendation to Require all semi-automatic rifles and semi-automatic shotguns to require an “E” category endorsement would not have affected most hunters or farmers who use bolt-, lever-, or pump-action rifles. However it would have — and still would — restrict the flow of military style weaponry and put an end to the sales of A-Category Assult Rifles which are truly MSSA weapons to anyone with the nous and inclination to buy a high-cap magazine.

If you remove the bar in the pink circle, you have an illegal Military-Style Semi-Automatic rifle.

Statutory gaps like these have been exploited in the past by people like Quinn Patterson, who acquired an ‘A Category’ semi-automatic using a friend’s firearms license and ‘converted’ it to an MSSA which he used to kill two people in July 2017 simply by adding a high capacity magazine to a legal gun.

Purchase of high-capacity magazines is unregulated and does not require a firearms licence — another change recommended by the 2017 select committee.

In 2018, Gun City owner David Tipple took court action over the Police decision not to allow new imports of AR15 semi-automatic rifles and parts.