Lawyers for the families of people killed in the Christchurch mosque attacks have told a hearing a coronial inquiry must examine the country's defective gun licensing regime.
Terrorist Brenton Tarrant opened fire on worshippers at two mosques in 2019, killing 51 people.
Lawyer Kathryn Dalziel has told the hearing to determine the scope of the inquiry there has been no detailed analysis of how the gunman got his licence, despite the Royal Commission of Inquiry.
She said he could not have amassed the guns he used in the massacre without a licence.
"If he did not have a licence he could not have got the guns that murdered 51 people. It really is so important to have this issue addressed."
Dalziel said some of her clients have gun licences themselves and were heavily scrutinised by police to ensure they weren't terrorists.
Families also want the coronial inquiry to examine whether the terrorist was acting alone, Dalziel said.
She said families she is representing believe the scope of the inquiry the Royal Commission into the 2019 massacre did not adequately probe whether the terrorist had help from anyone else.
The families want to see evidence that shows the basis on which police and the commission determined no-one else was involved.
"We have clients who say they witnessed somebody else present on the day that they believe was not the terrorist and they have been trying to get the information from the police about this.
"They have been trying to see... the videos that were taken outside the Al Noor Mosque."
Dalziel said the families also want to know whether fingerprints or DNA were taken from the guns at the scene, or whether the terrorist had support from associates online.
She has also asked the coroner to examine whether police who were first on the scene were confrontational or aggressive.
The coroner has already proposed examining the initial emergency response to the shooting in her inquiry into the deaths of the 51 people in 2019.
Dalziel said the terrorist was not the only person to point guns at people that day.
"We've had clients come to us and say they tried to speak to the police to say that the terrorist had left.
"They tried to tell them and they've been yelled at with guns pointed at them to sit down and shut up. They're injured yet they've been yelled at and so the timing of that might have saved lives."
She said the coroner must examine the time police took to secure the scene and the way they treated people that day.
Meanwhile, the coroner heard that a man fears his brother was alive but left for dead following the terror attack at the Al Noor Mosque.
Lawyer Anne Toohey has told the hearing that police believe Kamal Darwish died immediately after he was shot.
But she said there were two calls from Darwish's phone 20 minutes later, and a loveheart emoji was sent to his wife.
Toohey said Zuhair Darwish repeatedly rang his brother after the shooting and some calls appeared to connect.
She said Zuhair Darwish later went to Al Noor to tell police his brother could be alive, but officers threatened to arrest him if he did not calm down.
Along with the family lawyers, the coroner is due to hear from representatives of the Federation of Islamic Associations, Islamic Women's Council, St John Ambulance, Canterbury District Health Board, police, and Human Rights Commission.
The entire coronial hearing is being held remotely, via video link, because of the Covid-19 risk.
It is set down to last three days.
Before the hearing began the coroner declined to stand aside on the grounds of apparent bias.
Lawyers asked Coroner Windley to recuse herself because she was previously employed as a legal advisor to the police and worked as an investigator at the Office of the Inspector-General of Intelligence and Security.
They told a hearing this morning it was all a matter of perception.
While Coroner Windley acknowledged the victims' families have a deep sense of mistrust in institutions, there is nothing to suggest she cannot do her job in an impartial way.