Per New Zealand gun laws the alleged shooter was not allowed to possess an AR style rifle that could hold more than 7 rounds…hmmm…

"A Category firearms are those that do not fall into any other category, and are the vast majority of legally-owned firearms in New Zealand, and support a surprisingly wide number of types. For example semi-automatic AR-15 style rifles are permitted in this category provided they can only hold 7 or less rounds as well as meeting the other criteria."

https://en.wikipedia.org/wiki/Gun_laws_in_New_Zealand

"Suspect had a Category 'A' gun license," New Zealand police commissioner Mike Bush said at a press conference on Saturday. "We can report more fully at the conclusion."

https://www.businessinsider.com/new-zealand-gun-laws-will-change-prime-minister-says-2019-3