After Cascade won the licence, its shareholders stood to make nearly $60 million by selling the company’s assets — which consisted solely of the exploration licence — to White Energy for $500 million, but the deal fell over after a White Energy independent director raised concerns that the Obeid family might be involved.

In one intercepted phone call played before the commission, Mr Kinghorn was heard complaining about that director. “We just got to get there first ... then we’ll chop the arsehole’s head off,” he said.

Mr Kinghorn swung from snappish to belligerent during his turn in the witness box, describing as “utter, utter tripe” the suggestion that he had helped cover up who owned shares in Cascade Coal. He said he knew Mr Jones “as well as I know my wife” and had not asked him why he wanted Mr Kinghorn to hold his shares.

But he agreed that the Obeid’s shareholding in Cascade had left a smell about the deal, even after they were removed from the transaction. “Think of them as a dead cat,” he told the inquiry. “The dead cat’s gone but the smell is still around.”

The ICAC found that he had acted corruptly, but Mr Kinghorn appealed and in 2014 became the first person in 20 years to have a corruption finding overturned.

But Mr Kinghorn’s business past is returning on a second front, with the Australian Tax Office alleging that he avoided paying $30 million in tax over a period of two decades by engaging in a large and complex fraud.

He is facing three charges with each carrying a jail term of up to 10 years, and has pleaded not guilty to all three charges.

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