A coroner investigating the deaths of a Northland mother and daughter property inspecting duo and a tenant who killed them, has questioned Trade Me gun purchasing processes.
Wendy Christine Campbell-Rodgers, 60, and her daughter Natanya Kelly Campbell, 37, died from multiple gunshot wounds after being gunned down at a Whangārei Heads property rented by Quinn Lorne Patterson on July 26, 2017.
They had gone to the remote property about 10.30am with maintenance contractor Jeffrey Pipe to carry out a property inspection and do some repairs.
During a verbal exchange, Patterson got a gun and turned it on the group.
In her recently released findings Bell said Patterson and Campbell-Rodgers had a tense relationship from the outset, which worsened when Pipe was engaged to carry out property maintenance services at the address.
It further deteriorated when Campbell-Rodgers complained to police about a shooting target Patterson built on the property, then served notice on him to remove.
Police however were satisfied with Patterson's explanation that the target was used by his friend, Michael Hayes, to shoot pigs and targets.
Patterson did not have a firearms licence, for which police had assessed him as unfit.
Hayes had a firearms licence but illegally owned three military-style weapons with magazines.
Evidence showed Hayes and Patterson purchased firearms and ammunition through Trade Me, using Hayes' licence number but Patterson's account.
Hayes left some of his weapons, including the illegal military-style ones, at Patterson's address.
Bell's inquiries included whether the process of purchasing guns from Trade Me was robust enough.
Evidence was Trade Me took measures using its own internal auditing processes to try to ensure people who interacted with firearms listings were legitimately licensed.
Coroner Bell said she was satisfied with a report from a senior police liaison officer at Trade Me, Daniel Compton, about a firearms validation process "Licence Check" implemented by police and Trade Me since the Whangārei incident.
It enabled Trade Me to further check the firearms licence details entered by its members against a silo of the police firearms licence database.
The check is made in real-time and ensures only the holders of valid firearms licences are able to bid, buy or ask a question on firearms listings on the Trade Me website.
Compton emphasised the process took a number of years to fully implement and said it was a strong gatehouse to ensure that a purchaser interacting with a firearm or ammunition listing is a valid licence holder.
He also noted that there is still an offline process that individuals must complete before a firearm can be legally transferred to the new owner.
Police advised their inquiries did not establish any culpability for Trade Me sellers supplying firearms to unlicensed buyers.
The coroner also inquired as to whether 2019 changes to the Arms Act 1983, made in response to the Christchurch terror attacks, would prevent access to the gun used by Patterson.
Police armourer Terence Quirke told the coroner that due to the changed legislation, some of the firearms found at the Whangārei Heads property would be categorised as prohibited firearms.
Video footage showed the gun Patterson used to kill the Campbell women was a Gevarn .22 calibre semi-automatic firearm.
This weapon could still be lawfully obtained and possessed as a category A weapon by an appropriately licenced person after the April 2019 reform provided it was over 762mm in length and it did not have a magazine capable of holding more than 10 rounds.
Unfortunately it was Hayes (a former soldier and friend of Patterson's) who supplied Patterson with firearms, Quirke said.
(Hayes was subsequently sentenced to 12 months home detention after pleading guilty to three counts of unlawful possession of a military-style semi-automatic weapon (MSSA), three charges of supplying an MSSA to an unlicensed person, and three counts of supplying firearms to an unlicensed person.)
It was difficult to say if banning weapons of the type Patterson used would have made a difference since it was unlawfully obtained in the first place, Quirke said.