Police were justified in arresting a man who criticised them online for failing to act on information about the Christchurch mosque terrorist.
The Independent Police Conduct Authority (IPCA) investigated a complaint that the man's arrest and 48-hour detention was due to his criticism of the police and was unlawful.
However, the investigation found the man's arrest and detention were lawful but that it was unrelated to the criticism the man dished out.
Police Assistant Commissioner Richard Chambers said they accepted the IPCA's findings.
"Police take firearms offences extremely seriously, and the IPCA has determined the decision-making around the man's arrest and prosecution was appropriate, with the man's public comments having no bearing on the actions taken by officers."
Two days after the terror attacks on March 15, 2019, the man, called Mr X by the IPCA in their summary of events, became a person of interest after posting a recording on social media where he described witnessing the shooter's behaviour at a gun club.
Mr X said he was concerned about what he saw and warned police about him, however they failed to act on his warning.
On Saturday, March 23, police interviewed and then arrested Mr X, laying five charges of unlawful possession of firearms on him and kept him in custody over the weekend.
The day prior, police received a 111 call from a man called Mr Z who said Mr X had been in Auckland in possession of a Steyr rifle and multiple 30-round magazines.
The summary said attaching a 30-round magazine to a Steyr rifle meant it was configured as a military-style semi-automatic (MSSA) firearm.
On Facebook, police found a picture of Mr X holding an MSSA firearm with a 30-round magazine attached from 2016.
Later that evening, Mr Z's partner reported to police that she had returned home to find him dead in the house from a gunshot wound.
Mr X had been a firearms licence holder for a number of years but in February 2019 he voluntarily surrendered his licence to the Tauranga Police arms officer.
Mr X said he was surrendering the licence because he was under stress and "taking medication to help him balance his thoughts" due to issues with his former wife.
The arms officer did not require Mr X to surrender his firearms. He told the officer they were with a friend, Mr Y.
Following Mr Z's death, Tauranga Police were instructed to urgently locate Mr X and seize his firearms while inquiries were made into the death.
On the Saturday morning, Mr Y removed to rifles belonging to Mr X and surrendered them to police — the Steyr rifle was not there.
After Mr X — who was fishing — was located, police took him in for questioning and asked him about the whereabouts of his firearms and the photograph on Facebook of the MSSA.
Mr X said the photograph was taken overseas and that, in addition to the firearms in Tauranga, he also had firearms located on a farm in Waikato.
Police located a shotgun, two rifles, the Steyr rifle and also found and seized ammunition, bolts, magazines and a barrel from the property.
Mr X said the Steyr rifle was not configured as an MSSA and he had no 30-round magazines, of which none were found with any of Mr X's firearms.
Mr X said when he surrendered his licence four weeks earlier, the police did not give him any instructions about his firearms and was in the process of selling them.
After speaking with police, he was arrested for the unlawful possession of the Steyr rifle believed to be an MSSA weapon, and the ammunition found.
However, on the Monday morning, the arresting officer concluded there was insufficient evidence that Mr X intended to use the firearms for an unlawful purpose.
It was thought a lesser charge of possession in breach of licence was appropriate, however.
The IPCA thought it was reasonable for police to be concerned about Mr X's access to firearms, specifically the Steyr rifle, after Mr Z's death because he had recently surrendered his licence, citing emotional and psychological reasons for doing so.
Police were justified in arresting Mr X after discovering he was in possession of firearms while unlicensed and had firearms at a location unknown to them.
"The arrest was reasonable and based upon the information police had at the time about Mr X's licence status and the physical location of his firearms," the IPCA summary said.
"It was unrelated to Mr X's public criticism of police."
The IPCA was also satisfied that Mr X's detainment until the next available court sitting was lawful and based on an assessment of potential risk.
Mr X pleaded guilty to one charge of possession of firearms without a licence. He applied for, and was granted, a discharge without conviction.