Macquarie Radio’s Ray Hadley is not as prolific a letter-writer as his stablemate Alan Jones.

But he is known for his chummy relations with some politicians, notably the prime minister, Scott Morrison. Morrison had a regular Monday spot on Hadley’s show until April 2017, when the two fell out. But they patched it up in 2018 soon after Morrison got the top job.

Guardian Australia requested correspondence between Hadley and federal and NSW ministers under freedom of information laws.

The prime minister finally replied to the Guardian’s request on Christmas Eve and produced one letter written in July, in which he pushed back on criticism about the raids on journalists by the Australian Federal Police.

Whether this letter was sent to Hadley or Jones is unclear – the recipient was redacted – but it was more likely to be Jones, as he has been a critic on-air of the AFP actions.

Indeed, Jones was so incensed he emailed Morrison about it while he was overseas in June . Within half an hour a reply arrived direct from Morrison. These emails were not produced as a result of the Guardian’s freedom of information request, but Jones read most of it on air at the time.

It is likely there was more correspondence with both broadcasters, but the prime minister’s office invoked s4 of the Freedom of Information Act, which says only correspondence relating to the minister’s duties must be released.

Scott Morrison had a regular Monday spot on Ray Hadley’s show until April 2017, when the two fell out. But they patched it up in 2018 soon after Morrison got the top job. Photograph: Mick Tsikas/AAP

Another of 2GB’s regulars, the New South Wales Nationals leader, John Barilaro, did produce documents in response to the information request, which give an insight into how politics is played in NSW, and the way high-profile broadcasters are roped into campaigns.

On 6 August, Barilaro’s media adviser received an email from Hadley headed: “Adam Marshall doing the bidding of the Animal Justice Party.”

“Mate, ask barra what sort of lunacy this is,” Hadley wrote.

Copy and pasted into the email were three paragraphs from the Shooters and Fishers complaining about the agriculture minister, Adam Marshall, (also a National), who had asked the chair of a committee – a Shooters party MP – for a parliamentary inquiry into the exhibition of circus animals and dolphins and whales in NSW.

This was an unusual request from a National and had a whiff of a deal with the Animal Justice party.

Because the NSW government does not have a majority in the upper house, it must win over one of the minor parties to get legislation passed. It must deal either with the Shooters or Animal Justice. Shrewdly it cultivates both. But it’s not always easy.

Emma Hurst of Animal Justice explained that the party had been seeking an investment from the government in a sea enclosure at Coffs Harbour dolphin marine park, the only place that exhibits dolphins in NSW.

“We want the government to invest in sea pen facilities for retired animals and they said they would first need an inquiry,” Hurst said. “The wellbeing of circus animals was tacked on.”

The Shooters were horrified by Marshall’s request and forwarded the correspondence to Hadley, who then sent it to Barilaro with a “please explain”.

“Ms Hurst [one of two Animal Justice party MPs in NSW’s legislative council] is the deputy chair of the committee and given the close working relationship your government appears to be trying to cultivate with the Animal Justice party in this parliament, she may be willing to move this inquiry on your behalf, or on behalf of this government, though I would not be in a position to support such an inquiry,” the committee chairman, Mark Banasiak, a Shooter, wrote back to Marshall.

“Furthermore this proposal would have a natural and detrimental flow-on effect throughout rural and regional NSW, and will ultimately lead to the banning of rodeos and animal exhibitions at country shows around the state. It would also place at risk the world renowned Sydney Easter show.”

The next day Hadley was on air interviewing Banasiak, while making no bones about what he thought of Marshall.

The NSW agriculture minister, Adam Marshall. Photograph: Joel Carrett/AAP

“Of all the people that have been ministers in NSW parliaments since Federation, this bloke is the biggest joke of all time, Adam Marshall,” Hadley said on 2GB. “There have been some dopes in cabinet and ministry. I think he is on the podium as a gold medal winner when it comes to dopes.

“This will be the thin end of the wedge and that’s what the Nationals need to understand, once they get in bed with the Animal Justice party they’ll catch some fleas.”

Barilaro then texted Hadley, who read out the message on air, minus colourful adjectives.

There is no love lost between Barilaro and Marshall. The bad blood goes back to when Barilaro was seeking the leadership and Marshall was in another camp.

Barilaro’s response to Hadley remains a mystery.

Questioned about the missing correspondence, Barilaro’s staff said the minister routinely deleted messages and emails from his phone after reading them.

Sadly, the SMS to Hadley was one of the documents Barilaro deleted.

From what Hadley read out, Barilaro sought to convince him that the inquiry would be limited and cover only exotic circus animals and dolphin shows.

The letters quickly found their way to the Daily Telegraph, which piled on with the mockery of Marshall.

But despite Hadley’s criticism, the inquiry has gone ahead and will hold hearings in 2020. It has received several hundred submissions. Whether it leads to changes in the law or the investment in a sea enclosure being sought by the Animal Justice party remains to be seen.

Hurst insisted there had been no horse trading on other legislation.