A legal debate has erupted over mushroom killer Erin Patterson’s prison conditions, which a human rights advocacy group has branded “torture”.

Patterson, 51, has spent almost three years behind bars since being arrested in 2023 and last year found guilty of killing three members of her estranged husband’s family by serving them beef Wellingtons laced with death cap mushrooms.

WATCH THE VIDEO ABOVE: Mushroom murderer’s solitary confinement sparks torture claims

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International attention and extensive news coverage have led to Patterson being placed in solitary confinement for all but two hours every day for her own safety.

Advocacy group Justice Action said although isolating Patterson is meant to keep her safe, it has made her a “frightened woman” as she grapples with what fellow inmates say is a poor mental state.

“That’s the sort of behaviour that causes permanent damages. It’s torture, actually,” Justice Action co-ordinator Brett Collins told AAP.

Human rights advocates have described mushroom killer Erin Patterson’s prison conditions as ‘torture’. Credit: James Ross/AAP

University of Sydney Law Professor Thalia Anthony said solitary confinement means Patterson has very little access to open air and when she is outside, it’s usually no more than one hour a day in a very small courtyard.

“She doesn’t have contact with other people. It’s a very confined situation where her mental health is at serious risk,” Anthony said.

“What’s really needed is for her to have some social contact with other people physically, because without that, she’s feeling very hopeless about the situation,” Anthony said.

“It’s foreseeable that she will spend the remainder of her 33 years in solitary confinement and without any social access.

“So it’s going to have huge deteriorating effects on her mental health.”

An artist’s sketch of Patterson appearing in court via videolink for the second day of her appeal hearing. Credit: Anita Lester

She added that the prison must weigh up the risks of Patterson being attacked in general population, or Patterson harming herself while separated.

“There’s a very high suicide risk,” Anthony said.

“Given that she’s been in solitary confinement for almost four years and there’s evidence that her condition is deteriorating, the chance of death is likely.”

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