Radio star Jackie O Henderson’s lawyers are fighting for access to hundreds of confidential documents from the Australian Radio Network, including boardroom communications, WhatsApp messages and workplace investigation records, as her $80 million legal battle returns to the Federal Court.

The case is listed for a two-day hearing before Justice Ian Jackman in Sydney as the fallout from the spectacular collapse of Australia’s most famous breakfast radio partnership continues.

On Monday, the court heard how ARN directors sought information about interviews with staff and Kyle Sandilands before deciding to terminate Henderson’s lucrative broadcasting contract, after considering legal advice from two major law firms.

The behind-the-scenes deliberations were revealed during a two-day hearing before Justice Ian Jackman in Sydney, which Henderson and her best friend and manager, Gemma O’Neill, joined online.

Henderson and her company, Henderson Media, are suing ARN Media and its subsidiary Commonwealth Broadcasting Corporation over the termination of her contract on March 3, alleging unlawful adverse action and breach of contract.

ARN denies wrongdoing, arguing it was entitled to terminate the agreement after Henderson said she could no longer work alongside Sandilands, her long-time breakfast radio co-host.

According to ARN’s court submissions, Henderson and her company are seeking more than $80 million.

Monday’s hearing focused on whether ARN can keep hundreds of internal documents confidential on the grounds of legal professional privilege.

Henderson’s barrister, Vanja Bulut, argued ARN could not rely on its executives’ explanations for terminating the contract while withholding communications that might shed light on their reasons.

Among the disputed documents are messages exchanged by ARN’s non-executive directors through a WhatsApp group called ARN NEDs.

The court heard that director Belinda Rowe sent a message to the group on March 3, the day Henderson’s contract was terminated.

ARN has claimed legal professional privilege over the message.

The court also examined a separate text exchange that morning between Ms Rowe and ARN chairman Hamish McLennan.

Ms Rowe told the chairman she had spoken to an ARN executive the previous day to follow up on questions she and fellow director Brent Cubis had about interviews with staff and Sandilands.

McLennan replied: “OK thanks. I have to call you in about four hours. Does anything change our discussions?”

Ms Rowe’s response was redacted after ARN claimed legal professional privilege over it.

Henderson’s lawyers argued the exchange showed directors were seeking information about the investigation before deciding her future.

The employment dispute erupted after an explosive confrontation during The Kyle and Jackie O Show on February 20, when Sandilands criticised Henderson’s interest in astrology and questioned her ability to do her job.

He described her as “almost unworkable” and “off with the fairies”.

When Henderson told him she was offended, he replied: “Well, too bad if you are”.

Henderson subsequently stopped presenting the program.

On February 26, her lawyers sent ARN a formal complaint alleging persistent bullying and raising concerns about workplace safety.

The letter stated that “our client cannot continue to work with Mr Sandilands”, although Henderson indicated she was willing to present another program in a different timeslot.

ARN interpreted the letter as a refusal to fulfil her broadcasting contract.

The court heard ARN’s board met at 7am on March 2 to discuss its options, receiving legal advice and deciding to seek further written advice.

According to an affidavit from director Brent Cubis, he entered the meeting without a firm view about what the company should do but subsequently concluded Henderson’s contract had to be terminated.

The following day, legal advice from Herbert Smith Freehills Kramer and Arnold Bloch Leibler was circulated to directors.

ARN chief executive Michael Stephenson also prepared a memorandum recommending that the company accept what it alleged was Henderson’s repudiation of her broadcasting agreement and terminate the contract.

The memorandum was accompanied by Henderson’s complaint letter, her broadcasting agreement and legal advice.

A board subcommittee then met, with lawyers present, and approved the proposed course of action.

Ms Bulut argued that Mr Stephenson’s reasons for recommending termination were particularly important because the board acted on his advice.

“It was his recommendation that was actioned by the board, and so he materially contributed,” she told the court.

The court also examined evidence from ARN director Alison Cameron, who said she was prepared to support terminating Henderson’s contract and issuing a breach notice to Sandilands, provided the other directors were satisfied with the legal advice.

Ms Cameron believed Henderson’s refusal to work with Sandilands meant the contract could not continue.

Another major dispute concerns ARN’s investigation into the February 20 confrontation.

The court heard ARN’s people team initially proposed an investigation to establish what happened, hear different perspectives and determine appropriate outcomes.

However, ARN chief legal officer Jeremy Child said in an affidavit that he arranged an investigation to help the company obtain legal advice after external lawyers were engaged on February 24.

Henderson’s lawyers are seeking access to investigation records, including staff interview notes, while ARN argues that documents prepared for the dominant purpose of obtaining legal advice are protected by privilege.

ARN’s separate challenge to Henderson’s documents has narrowed to five, while it has abandoned its privilege challenge involving documents produced by Ms O’Neill under subpoena.

Tom Blackburn SC, representing ARN, argued the company was required to explain why it terminated Henderson’s contract but should not lose its right to keep legal advice confidential simply because its reasons were being challenged.

ARN maintains its directors believed Henderson would no longer fulfil her broadcasting obligations and that the network should not have to pay her the same remuneration to present a different program.

Henderson alleges she was unlawfully punished for exercising her workplace rights by complaining about Sandilands’ conduct and raising safety concerns.

Under a landmark agreement struck in 2023, Henderson Media was entitled to approximately $9.4 million annually plus revenue sharing, according to ARN’s submissions.

The deal was intended to keep the famous broadcasting duo on air until the end of 2035.

ARN argues Henderson’s refusal to continue presenting the breakfast program entitled it to terminate the agreement. Henderson disputes that claim.

The litigation continues despite ARN reaching a separate settlement with Sandilands in June, ending his own Federal Court proceedings.

Sandilands secured a $12.09 million cash payout and a further $1.5 million in advertising support for his new media venture.

Henderson’s trial, originally scheduled to begin on October 12, has been postponed until April 27 next year, when it is listed for nine hearing days before Justice Wendy Abraham.

The interlocutory hearing before Justice Jackman continues.