Heather du Plessis-Allan talking about the police decision not to charge her

A gun shop owner says he is "80 per cent certain" he will pursue a private criminal prosecution against Heather du Plessis-Allan, after police decided to drop gun charges against the journalist.

TV3's Story co-host has been let off the hook by police who, after an investigation, opted not to charge du Plessis-Allan for purchasing a gun in an episode of the show, ostensibly to expose loopholes in how guns can be bought online.

Police announced on Wednesday afternoon they instead issued formal warnings to three TV3/MediaWorks staff.

Story Segment from Story in response to the police search on Heather du Plessis-Allan's apartment.

On Wednesday night's episode of Story, du Plessis-Allan and co-host Duncan Garner said they were grateful to police.

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"We want to say thank you to the police. We understand why they needed to investigate and we welcome the outcome of the investigation, of course," du Plessis-Allan said. "But most importantly, we want to say thank you to the police for so quickly shutting down the flaw that we exposed. They did that within hours of us calling them in October, and that was the point of doing our story, so thank you." Disappointed by police, Gun City owner David Tipple said he was looking to bring his own case against the television presenter.

SUPPLIED Story co-host Heather du Plessis-Allan was investigated over the mail-order purchase of firearms from Gun City for a story - but police have announced they will not pursue charges against her.

"It's really disappointing," Tipple said of the police decision. "I was hoping for something that would stop a ratings chaser doing this again.

"They got ratings. Legitimate gun owners need to be protected from media stunts like that," he said.

"At the end of that, police decide not to prosecute - it's sad."

TV3 Heather du Plessis-Allan refutes police claims about the gun purchase.

Tipple was working with "specialist firearms lawyer" Nicholas Taylor, he said.

"We haven't prepared a case but that's something we are looking at now. We are 80 per cent that we will."

Auckland city district commander Superintendent Richard Chambers said police took legal advice and a review of the case was undertaken by a senior officer.

TWITTER Story co-host Heather du Plessis-Allan said buying a gun was so easy it was like finding money on the ground.

"Police are satisfied that in this instance, there is no evidence that the acquisition of the firearm was for a sinister purpose, a factor which was taken into consideration in reaching this decision," Chambers said.

Changes were made to the way guns were bought and sold after the Story episode on October 21, 2015, which showed the purchase of a .22 rifle from Gun City.

At the time, du Plessis-Allan said the purchase was made in the public interest and showed the rules around mail ordering guns should be tightened.

MAARTEN HOLL/Fairfax NZ Barry Soper and partner Heather du Plessis-Allan's home searched after gun purchase.

"What we've uncovered has exposed how worryingly easy it is to get a gun when you shouldn't be able to," she said.

Her journalist husband Barry Soper said the police decision was "clearly a great relief to Heather".

"She's been living with this now for some months. I think police have taken a reasonable path here and they've done a good investigation and the best thing about their statement to me is that they say they don't stand on the rights of journalists to investigate matters such as this."

A complaint to police about du Plessis-Allan's action was made the night the story aired, alleging that false details had been used to fraudulently obtain a firearm.

The Wellington home du Plessis-Allan shares withSoper was raided in December as police investigated whether she should face charges.

Making an unlicensed purchase of a firearm is an offence which carries a sentence of up to three months' imprisonment or a fine of up to $1000.

Another charge police stated early on they were looking at, obtaining by deception, carries penalties ranging from three months to seven years in jail, depending on the value of the item obtained.

Story broadcaster MediaWorks backed du Plessis-Allan's actions throughout the saga.

A MediaWorks spokesperson said in a statement the intention behind the story "was to put a spotlight on an issue rather than any one individual business".

"Story regrets any impact that may have inadvertently been caused to Mr Tipple as a result of the story."

Police said on Wednesday their investigation focussed on the actions of MediaWorks staff members in the creation of a forged document and the use of the document to obtain a firearm.

They had become involved because MediaWorks staff had sought to surrender a firearm that had been illegally purchased from a licensed Auckland firearms dealer, Chambers said.

The story and subsequent investigation provoked national debate about gun laws and when journalistic privilege extends to breaking the law to expose issues in the public interest.

Chambers said police were aware of some commentary suggesting the story was in the public interest and should not have been investigated.

He said the question of public interest did not determine whether police should proceed with a criminal investigation - instead such considerations were applied at the end of an investigation.

"Police view this case as no different to any other matter where criminal offending is disclosed. The circumstances of individual cases are routinely assessed to ensure that an appropriate investigation is initiated.

"We would also like to be clear that the freedom of journalists to report on any matter is fully accepted without question by police.

"The law, however, applies equally to everyone, including members of the media and police do not accept that it is appropriate to commit a criminal offence purely to publicise the ease with which something can be done."

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