Nine secretly paid $700,000 to silence a disgruntled key witness from going public with allegations against its star reporter in the Ben Roberts-Smith war crimes defamation case.

The witness, who remains confidential and is known as Person 17, was paid the cash for her silence after sending a series of explosive emails to Nine executives claiming journalist Nick McKenzie had treated her poorly and wrongfully obtained Mr Roberts-Smith’s privileged legal advice during the case.

The woman, alleged by Nine to be a domestic violence survivor, also begged McKenzie to protect her from harmful stories being published in the media company’s newspapers, known previously as Fairfax.

Know the news with the 7NEWS app: Download today

When he assured her she would be protected, Person 17 asked how he could guarantee that, McKenzie allegedly replied: “I am Fairfax.”

According to Sky News journalist Sharri Markson, Nine paid Person 17 the $700,000 hush money shortly before the commencement of Mr Roberts-Smith’s appeal against the decision in his defamation case.

In an email, sent to Nine executive Tory Maguire and executive counsel Larina Alick in the lead-up to Mr Roberts-Smith’s appeal against the media company in May 2023, the woman claimed McKenzie admitted receiving confidential legal strategies from the former SAS soldier’s ex-wife Emma Roberts and her friend Danielle Scott.

“I also know these women were passing on confidential and privileged information to Nick as far back as mid-late 2020,” the email says, according to Sky.

A recording of a conversation between Person 17 and McKenzie has since emerged, in which the reporter is captured saying: “I shouldn’t tell you. I’ve just breached my f…... ethics in doing that.”

In the recording, McKenzie claims they had been “actively briefing us on his legal strategy in respect of you ... we anticipated most of it. One or two things now we know.”

Nine responded to the emails from Person 17 in which those recordings were referred to by paying the woman $700,000 to silence her in the lead-up to Mr Roberts-Smith’s appeal against the network.

After Sky News broadcast the secretly recorded conversation in March, Nine threatened to sue Person 17 — who had been in a relationship with Mr Roberts-Smith — and demanded she repay the $700,000.

The letter from Ms Alick accused Person 17 of leaking the audio recording to Mr Roberts-Smith and Markson at Sky News.

“The Nine Group request that your client refund the Settlement Sum in full within 14 days,” it states.

“If payment is not received by Monday, 7 April 2025 the Nine Group will commence legal proceedings against your client for payment of the debt under contract law.”

Sky also reported it had obtained Person 17’s unfiled statement of claim, in which she alleges McKenzie had accessed inside information on Mr Roberts-Smith’s legal strategies.

“By some time prior to 24 April 2021, the respondents had gained unauthorised access to material over which BRS had a claim of legal professional privilege,” it states.

“On 24 April 2021, the respondents fixed a prospective witness in the Defamation Proceeding (namely, P17) with knowledge of that unauthorised access.”

According to the report, Person 17 sent a return legal letter rejecting Nine’s allegations and denying that she had leaked the audio recording.

After the emergence of the audio, Mr Roberts-Smith, who lost his seven-year defamation lawsuit against Nine in 2023, managed to have the appeal hearing into the war crimes finding re-opened, arguing that McKenzie’s alleged misconduct constitutes a miscarriage of justice.

The Federal Court last Friday reserved its judgment on whether to grant a retrial.

After five hours of cross examination in the Federal Court last week, barrister Arthur Moses, who is representing the Victoria Cross recipient, called McKenzie a liar whose evidence could not be trusted.

Mr Roberts-Smith originally sued Nine for defamation after being accused of war crimes during his deployments as an SAS soldier in Afghanistan.

According to the Sky report, the court heard that McKenzie was aware Person 17 had previously raised concerns with him about providing Mr Roberts-Smith’s legal strategy. But he denied knowledge of legal correspondence between Nine and Person 17.

McKenzie also said in court that none of the information provided by Mr Roberts-Smith’s ex-wife via Ms Scott was privileged and was no more than “gossip” between friends that had been passed on to him.