Mr Medich, who celebrated his 69th birthday on Tuesday, had pleaded not guilty to the murder of Cremorne wheeler dealer Michael McGurk and the subsequent intimidation of his widow Kimberley.

Shortly before 4 o'clock on Thursday afternoon, the jury of seven men and five women sent a note to Justice Geoffrey Bellew indicating they had not been able to form a unanimous verdict. "This does not look likely to change," the note said.

Because the voting patterns disclosed to the judge were so far apart, he decided it would be pointless to offer them a chance to reach an 11-1 majority verdict.

The accused frowned while his daughter Pamela cried.

Mrs McGurk comforted her two daughters in the King Street court room as they wept.

It had all come down to the word of one man.

The Crown's star witness and Mr Medich's once close friend, Fortunato "Lucky" Gattellari, gave evidence that Mr Medich was "the big boss" who had ordered and paid for the 2009 murder of Mr McGurk.

The NSW Supreme Court heard that Mr Medich was enraged over a string of lawsuits in which he and Mr McGurk were embroiled.

Accusations of fraud flew back and forth with each claiming the other owed him millions of dollars. The pair were feuding over soured property deals, a loan company and mortgages linked to a house in Point Piper.

According to Gattellari, by early 2009, Mr Medich had had enough.

After a series of losses in court, Mr Medich complained bitterly to Gattellari that Mr McGurk was making "a fool of me, the laughing stock of the eastern suburbs".

"I want it done," Mr Medich allegedly told Gattellari.

Gattellari, a former professional lightweight boxer and one-time Qantas steward, told the court he hoped Mr Medich's desire for the ultimate revenge would blow over. But Mr Medich allegedly continued to badger him about whether he had found a prospective hitman.

Gattellari's lifestyle, which kicked off each morning with a cognac and cigar, was funded by Mr Medich's astonishing largesse. Not only did Mr Medich fund their daily boozy lunches, visits to brothels and overseas jaunts, Mr Medich also poured $16 million into Gattellari's failing electrical companies.

With his younger brother Roy, Mr Medich had made his fortune developing industrial sites in Liverpool.

In 2008, the brothers fell out and, after selling their interest in Leichhardt's Norton Street Plaza for $112 million, Roy and Ron went their own ways.

Around the eastern suburbs, Mr Medich had the unfortunate nickname "Cottee's" after the Thick'n'Rich ice-cream topping. The portrait painted of Mr Medich's business acumen throughout the trial was not a pretty one. He squandered millions of dollars on questionable business deals, with dubious partners and without any documentation.

He invested in an Aboriginal funeral business (which was shut down by the corporate regulator), a failed property development with an Aboriginal land council (which was referred to ICAC) and had offered a $25 million loan facility to a pay-day lending company.

On top of that, there were the millions of dollars he had invested in Mr McGurk's property deals, the $16 million in Gattellari's companies as well as a host of unsecured and undocumented personal loans to associates and hangers-on.

The cycle of Mr Medich's business failures meant that whoever became his new "best friend" was asked to try to recoup Mr Medich's investments, usually by way of menace, according to the evidence.

Gattellari's predecessor was the Scottish-born Mr McGurk who was dispatched to Hawaii by Mr Medich to threaten Paul Mathieson, the founder of Amazing Loans, the court heard.

In November 2008, Mr McGurk firebombed the home of Adam and Sally-Anne Tilley in Point Piper.

The waterfront house in Wolseley Road had been owned briefly by Mr Medich and his then-wife Odetta. The Medichs had found a superior residence up the road so they lent the Tilleys the money to buy their redundant mansion.

However, the Tilleys fell behind with the payments so Mr Medich handed this problem to Mr McGurk to fix.

When legal action against the Tilleys failed, Mr McGurk went to plan B, firebombing their house. Mr Medich posted his $100,000 bail when Mr McGurk was charged with arson in January 2009.

The charges were dropped not long before Mr McGurk was murdered.

But within weeks Mr Medich had withdrawn the bail surety and the duo were now at war. This meant the vacant position of consigliere to Mr Medich was free for Gattellari to fill.

Keen to keep his benefactor happy, Gattellari said he recruited brothers Haissam and Bassam Safetli to murder Mr McGurk.

The brothers, who were doing odd jobs for Gattellari's electrical company, set the price for murder at $300,000 plus expenses.

"F---, that's a lot of money," Mr Medich complained, according to Gattellari.

After initially baulking at the cost, Mr Medich eventually forked out between $500,000 and $600,000 for the murder of Mr McGurk, the court heard.

And, when Mrs McGurk didn't pay the millions Mr Medich felt her husband owed him, Mr Medich instructed Gattellari to have her threatened.

Gattellari's evidence was that he organised the murder on behalf of Mr Medich. However, complicating matters for the Crown was that he was recently charged over trying to extort $15 million from Mr Medich to change his evidence (using the now convicted murderers Roger Rogerson and Glen McNamara as go-betweens).

"Lucky Gattellari is never going to be awarded Australian of the Year," Crown prosecutor Gina O'Rourke, SC, told the jury.

"But who do you go to if you want to arrange a murder and an intimidation?" she posed. "If you are the accused, ladies and gentlemen, you go to Lucky Gattellari. That is exactly what he did."

On the evening of September 3, 2009, Haissam Safetli, then 45, and Christopher "The Kid" Estephan, 19, fortified with Jim Beam bourbon from the local Cremorne bottle shop, waited for Mr McGurk.

At 6.25pm Mr McGurk and his nine-year-old son arrived home with a takeaway chicken and chips for dinner. As Mr McGurk alighted from his Mercedes he was shot in the head.

His terrified son ran up the side path of the family's Cremorne home screaming, "Mummy, mummy, dad's been hurt. There was a pop and there's blood."

Mrs McGurk rushed out to find her husband, half out of the car, a bullet hole behind his right ear.

At 8.03pm, Bassam Safetli sent a text to Gattellari's right-hand man Senad Kaminic, saying: "Job's done."

Kaminic told an earlier hearing that Bassam complained to him about his brother's stupidity, including that, on the night of the murder, Haissam had burned his clothes, forgetting that some of the murder money was still in his pocket.

"Look at this idiot. And they believe it was a professional hit," Bassam is alleged to have told Kaminic.

The Director of Public Prosecutions will now decide whether Mr Medich will face a new trial, a likely prospect according to his barrister Winston Terracini, SC. Mr Medich left the court without speaking.

Shouts could be heard from the jury room after they left the courtroom. Whether it was from relief or joy was not clear.