In extraordinary comments in an extensive interview with the ABC's Four Corners program on Monday night, Mr Lawler has predicted that his decision to go public will see him "characterised as that scum bag, crook, fraudster and at the very best somebody who's been bewitched by an evil harridan, mainly Kathy. That I'm c--t struck and that I have been utterly taken in by somebody who is a serious crook". Michael Lawler and Kathy Jackson. And Mr Lawler has also revealed that he has about 60 recordings of private conversations with Fair Work Commission president Iain Ross dating as far back as 2012. The recordings include detail of discussions about Mr Lawler's extended period on sick leave, during which he has given legal advice to Ms Jackson, and reveal Mr Ross promising to "take responsibility for any amounts of sick leave you seek, there's no cap or anything like that". Mr Lawler has been under fire for taking more than nine months' sick leave while Ms Jackson fought a civil case brought against her by her former union.

He concedes that Mr Ross will likely be "very annoyed indeed" at the covert recording. Fair Work Commission President Iain Ross. Credit:Jesse Marlow Ms Jackson was found guilty in a civil case that ended in August of misusing her position as head of the union to fraudulently gain financial advantage and ordered to pay about $1.4 million. She was found to have spent hundreds of thousands of dollars on unauthorised expenses including clothes, fine dining, grocery and liquor shopping, personal mortgage repayments, as well as flights and hotels while on multiple overseas vacations. In the program, Ms Jackson that she did not take "anything like" $1.4 million from the HSU, nor anything from the HSU "I wasn't entitled to. And I do want to qualify it like that because they'll come out and say 'yes, but you did spend this money on travel' - yes I did, I was entitled to that."

Ms Jackson insists she was entitled to up to $28,000 in travel entitlements and that she had this undertaking in writing, while head of the HSU. Mr Lawler concedes that the written evidence of this entitlement is "gone, it's not in the public domain. All the minutes, all bar eight sets of minute, meeting-minutes are missing." And pressed about the so-called "crooked" transaction - which saw money transferred into a joint mortgage account held Ms Jackson held with her ex-husband Jeff Jackson, and which allegedly flowed on in to Jackson and Lawler's Wombarra, NSW home, Mr Lawler makes a concession. "The last time I did a count it was in the order of $50,000 dollars and they are the transactions that represent the payment of monies from the NHDA, the slush fund of the Number Three branch, into the Jeff Jackson account or their joint mortgage account and, I know what her explanation for those transactions is, it's not a very palatable explanation, but it's an explanation none the less and it'll be given at some point," he says. Ms Jackson says that she did not know at the time that money transfer was improper but "with the benefit of hindsight, yes".

But the current HSU national secretary, Chris Brown, says Ms Jackson "was of the view that if she blew the whistle and was seen to be the person, ah, cleaning up the union then any wrongdoings that she had done, ah, would be overlooked and exonerated". In the program, Mr Lawler also says that he encouraged Ms Jackson to become a whistleblower, and that he worked on her legal case while on leave. Earlier on Monday, Workplace Minister Michaelia Cash announced that Peter Heerey QC, a former Federal Court judge, would lead the independent investigation of complaints levelled against Mr Lawler. As a vice-president of the Fair Work Commission, Mr Lawler can only be removed by a vote by both houses of Parliament. Mr Heerey served on the Federal Court between 1990 and 2009 and has now returned to private practice as a barrister at the Victorian Bar.

"It is essential that public confidence is maintained in the institution of the Fair Work Commission," Senator Cash said. "I will not be commenting on the specific complaints before the independent investigator has had an opportunity to report back to me on this matter." Follow us on Twitter