The messages came from police documents, compiled prior to Lehrmann's criminal trial, to which he and few others allegedly had access.

Mr Collins described Lehrmann having leaked the messages as the "obvious explanation" as to how they reached Mr Auerbach.

"The conduct, we submit, that's been exposed before Your Honour over the last day and a half or so, goes to the core of Mr Lehrmann's honesty and integrity," Mr Collins told the court.

Mr Auerbach also told the court he was tasked with babysitting Lehrmann in order to secure a confidential interview for Seven's current affairs program Spotlight.

During that period Mr Auerbach alleges he witnessed Lehrmann buying cocaine and ordering sex workers to a Sydney hotel which was paid for by Seven.

He said discussions took place around Lehrmann being paid in the order of $200,000 to appear in the exclusive, tell-all interview to respond to allegations he raped Ms Higgins in Parliament House.

Lehrmann says there was no sexual activity between the pair.

His 2022 criminal trial in the ACT was derailed due to juror misconduct, with prosecutors dropping the charges against him over fears for Ms Higgins' mental health.

He has also denied providing Seven with any information for the Spotlight item, besides his interview.

Seven has also broadly denied Mr Auerbach's allegations, labelling them "false and misleading" and adding that it did not reveal journalists' sources.

Mr Auerbach told the Federal Court on Friday he met Lehrmann's representative John MacGowan in October 2022, to discuss the interview.

"I was in Canberra for the criminal trial between Mr Lehrmann and Ms Higgins," the former TV producer said.

"We talked about the fact that Mr Lehrmann had many legal fees and needed to be compensated."

Rather than pay Lehrmann directly, they discussed paying the money into a trust under a different name, the court was told.

Mr Auerbach said in agreeing to the interview two days later, Lehrmann told him he was glad the producer "wasn’t sitting with the rest of the feminazis in the press pack".

Seven also paid for expensive dinners, hotels, massages and a golf trip for Lehrmann, as well as renting him a house in Sydney's Randwick, according to an affidavit from Mr Auerbach.

A $750 invoice paid by Seven was understood by Mr Auerbach to cover "Mr Lehrmann’s expenditure on cocaine and prostitutes".

"He indicated to me he needed to replenish his bank account after the bender," the ex-Seven producer told the court.

Since Lehrmann was not an employee of Seven, the payment was listed under "pre-production expenses" rather than "per diem" as was previously discussed, the court was told.

“We had to come up with another category that finance would allow," Mr Auerbach said.

In an affidavit, Mr Auerbach said he was also sent messages between Ms Higgins and a former boyfriend, and later messages between her and journalist Peter Fitzsimmons, which made up part of the confidential police file.

Mr Auerbach said he was sent photographs of a document on a laptop showing screenshots of text messages between the pair.

He claimed the photographs were taken by Spotlight executive producer Mark Llewellyn, whose image he could recognise reflected on the laptop screen.

According to Mr Auerbach, the trio also had dinner at Sydney restaurant Spice Temple in March 2023, during which Mr Llewellyn asked Lehrmann if he had documents for the criminal proceedings, to which he replied that he did.

Lehrmann accompanied the men to Seven's office, where he made copies of some of an estimated 500 pages of double-sided documents from the criminal case, according to Mr Auerbach.

"I viewed some of the documents that were being copied and could see that they were exhibits from the applicant's criminal proceedings," Mr Auerbach said in his affidavit.

"I saw, by way of example, Ms Higgins' text messages."

According to Mr Auerbach, Lehrmann told him on a number of occasions that evening he would only get access to the documents "when you sign me".