In her closing address to the jury, Crown Prosecutor Gina O'Rourke, SC, said that Mr Medich wanted his "business foe" murdered because his relationship with McGurk was toxic.

Several witnesses gave evidence that Mr Medich was consumed by anger over McGurk fighting him in court for millions and millions of dollars and that at every turn Mr Medich was losing.

He turned to his close friend Lucky Gattellari to get rid of McGurk on his behalf, the jury heard.

The court heard that Gattellari and Mr Medich where "joined at the hip" and that their relationship grew even closer after the September 2009 murder of McGurk, which Gattellari has confessed to orchestrating on Mr Medich's behalf.

The "mutual dependency" and trust between Mr Medich and Gattellari saw the wealthy property developer plough $16 million into Gattellari's failing electrical businesses.

The two men lunched almost daily and attended massage parlours together.

All that changed in the days before Gattellari's arrest on October 13, 2010, when Mr Medich, who talked almost daily to Gattellari, refused to have anything to do with him.

The pair knew that "the gig was up" and the police were closing in, said the prosecutor.

On the day of Gattellari's arrest, Ms O'Rourke told the jury that Kim Shipley, an accountant at Gattellari's electrical business, asked Mr Medich if he had been involved in the murder.

"Don't be bloody silly. Watch what you say, the walls have ears," Mr Medich is alleged to have said.

Mr Shipley told the jury Mr Medich's hands were shaking.

Gattellari, who had been charged with murder, got a message to Mr Medich requesting $1m for his impending legal fees, only to rebuffed.

Gattellari's view was that "the accused owed him big time," Ms O'Rourke said.

Within days Gattellari began co-operating with the police and several weeks later Mr Medich was himself arrested. Gattellari received a substantial discount on his sentence in return for giving evidence against his once close friend, who has pleaded not guilty to both charges.

The jury heard that Mr Medich was the only one who had a motive to murder McGurk and then to intimidate his wife Kimberley when she didn't settle her late husband's legal actions against Mr Medich.

Mrs McGurk told the jury that the man on August 8, 2010, a man had come to her house telling her not to be a "conman" like her husband and to pay his debts.

The jury has heard that the only person chasing Mrs McGurk for money was Mr Medich.

Ms O'Rourke told the jury that the "accused was guilty beyond all reasonable doubt" of both the murder of McGurk and the intimidation of his wife.