The terrorist's ability to obtain the guns he used in the Christchurch terror attack will be examined at an inquest.
The second-phase inquest into the massacre of 51 worshippers at Al Noor Mosque and the Linwood Islamic Centre in March 2019 will examine firearms laws before the attack.
Deputy Chief Coroner Brigitte Windley will examine how the terrorist came to obtain his firearms licence; whether police should have elicited information which would have led them to reject his application; and whether there were any errors, failures or deficiencies in their assessment.
The coroner's first phase inquest covered 10 issues relating to the events of 15 March 2019 and the response of emergency services to the massacres.
It took just minutes for the terrorist to leave 44 worshippers dead or dying at Al Noor Mosque as he possessed two semi-automatic centrefire rifles, as well as a multitude of high-capacity magazines, two shotguns, a lever-action rifle and a bolt-action rifle.
He then drove to the mosque in Linwood, where he killed seven more people.
Brenton Tarrant was able to obtain a New Zealand's firearms licence after a gaming friend - who was aware of his extremist political opinions and his racist and Islamophobic beliefs - and the friend's father acted as referees for the process.
He had originally planned to use his sister as a referee, but the licensing clerk rejected that possibility as she lived in Australia and could not be interviewed face-to-face.
The terrorist first submitted an application to obtain a firearms licence only 15 days after arriving in New Zealand in August 2017.
At the time of the attacks, he only held a standard A-category licence but by inserting the high-capacity magazines into the semi-automatic centrefire rifles he had turned them into restricted E-category military-style semi-automatic rifles.
The purchase of such high-capacity magazines was unregulated at that time.
Windley will examine this so-called military-style semi-automatic firearm loophole.
She will also address whether police made any "operative errors, failures, or deficiencies" in assessing whether the terrorist was a fit and proper person to hold a firearms licence, under the licensing process as it stood in 2017; whether police could and should have asked the terrorist and his referees questions designed to elicit whether he held extremist political, racist or any other beliefs or views; and on the basis of the process which was taken whether he should have been assessed as a fit and proper person and granted a firearms licence.
The coroner will also examine how firearms licensing laws as they existed in March 2019 contributed to the attack, and take a counterfactual analysis as to whether the terrorist could have obtained a firearms licence and carried out the attack he did if different decisions were made by police and regulators.
The inquest is set down for three weeks, with about 15 witnesses expected to be called.