Prosecutors have taken a flawed and selective approach to the evidence against mushroom cook Erin Patterson, her lawyer claims.

Barrister Colin Mandy SC began his closing arguments in the Victorian Supreme Court on Tuesday afternoon as his client’s triple-murder trial reached its final stages.

At the start of his address, Mandy argued the prosecution had been flawed and selective in highlighting the evidence that suited its case.

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.

The Pattersons and Ms Wilkinson all died after consuming the July 29, 2023, beef Wellington lunch at Erin Patterson’s home in regional Victoria, while Ian survived.

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

Mandy began his address about 12.40pm on Tuesday, after Crown prosecutor Nanette Rogers SC concluded her final statements.

Rogers told the jury it should find Patterson guilty of all charges because she deliberately sourced death cap mushrooms and served them to her guests.

She pointed to Patterson’s alleged incriminating conduct after the lunch, noting her decision to dump her dehydrator and carry out factory resets on her mobile phone.

Patterson lied about giving her children leftover beef Wellington with the mushrooms scraped off, Rogers also alleged.

She said Patterson made up the story because she knew she had included death cap mushrooms in the lunch.

“[She] thought if she said she also fed it to her children, it would deflect any suspicion,” Rogers told the jury.

Patterson lied about sourcing the mushrooms from an Asian grocer in Melbourne, Rogers also said.

She told the jury that Patterson gave 10 different accounts about where she bought the mushrooms in the days after the lunch, with the locations changing repeatedly.

Patterson knew the mushrooms did not come from an Asian grocer and she continued to peddle the false story to deflect blame, Rogers alleged.

-AAP