Accused killer Erin Patterson’s account of the deadly beef Wellington lunch did not unravel despite being cross-examined for days, her barrister says.

Colin Mandy SC told the Victorian Supreme Court jury his client had the right to stay silent in her triple-murder trial but she instead chose to face questions from the prosecution.

“She decided to give evidence and to subject herself to several days of cross-examination by a very experienced barrister,” Mandy said.

Patterson, 50, has denied she intentionally poisoned her former in-laws Don and Gail Patterson, Gail’s sister Heather, and Heather’s husband Ian Wilkinson.

Don, Gail and Heather all died after consuming the July 29, 2023 beef Wellington lunch served by Patterson at her home in regional Victoria, while Ian survived.

Patterson has pleaded not guilty to three charges of murder and one count of attempted murder.

Mandy told the jury Patterson was not only being scrutinised by those in the courtroom during her cross-examination, but also the whole world.

He maintained that despite more than 20 hours of “surgical” questioning from crown prosecutor Nanette Rogers SC, Patterson’s account did not unravel.

Mandy noted Patterson had spoken to 21 people within 24 hours after the lunch, including medical professionals, health department staff, child protection workers and police.

Each person asked different questions depending on the focus of their investigations but Patterson’s comments to each of them were the same in “every meaningful way”, Mandy said.

“The answer of the question changed depending on who was asking the question,” he said.

Patterson was also forthcoming in her admissions that she lied to the lunch guests about being diagnosed with cancer and that foraged mushrooms might have been in the meal, Mandy said.

The barrister’s closing address is due to continue today before Justice Christopher Beale gives his final directions to the jury.

The judge has already indicated he will not begin his instructions until Monday, with the jury to begin deliberating on Tuesday afternoon at the earliest.