The estranged husband of triple murderer Erin Patterson was not informed of his right to not give evidence in his wife’s trial until he had already started giving his testimony.

Just three days into Patterson’s 10-week trial, the hearing threatened to derail.

In a jaw-dropping moment, Simon Patterson was told — for the first time — that he had the option to sit out of the proceedings.

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“There is a matter I need to raise with you in the absence of the jury,” Justice Beale said to Patterson, as the court resumed following a lunch break.

“I made certain assumptions and I just want to confirm that those assumptions are correct.

“The spouse of an accused person has a right to object to giving evidence. I’ve assumed, that, from the history of this matter, you’ve been informed of that right previously and were willing to give evidence nonetheless.

“Now, are those assumptions correct?”

Simon responded “no”, prompting quiet gasps from members of the media.

Justice Beale offered Simon the opportunity to have some time to consider whether he was still willing to participate, but the father-of-two said he was happy to proceed.

“I’m willing to give evidence,” he said.

“I think if I had of been offered that before, I still would have said the same thing. I’m quite comfortable about that.”

However, Simon took the opportunity to reveal to Justice Beale the personal toll the trial had taken on him.

He told the court he had struggled with not being able to follow the trial, as he was not permitted to sit in court to watch the proceedings until he had finished giving testimony.

“The legal process has been very difficult,” he told Justice Beale.

“I have a lot to grieve and am grieving a lot about all this stuff here, as I’m sure you can imagine.

“One thing that is really difficult is not being able to follow along throughout the trial.

“Your honour, would you be able to make available, after all the legal proceedings are finished, the transcripts for those hearings for me to be able to ... to help me with that grief?”

Justice Beale said he didn’t “take a negative view” of Simon’s request, but asked that he be given some time to decide.

Justice Beale: “Is that alright?”

Simon: “Thank you, your honour. Yes.

“For me, it is really, really important, so I thank you that you’ll consider that.”

After spending almost two months listening to more than 50 witnesses give evidence, the 12 jurors overseeing Patterson’s case on Monday found her guilty of three counts of murder and one count of attempted murder.

Patterson’s former parents-in-law, Don and Gail Patterson, both 70, and Gail’s sister, Heather Wilkinson, 66, died after eating beef wellingtons laced with death cap mushrooms at her home in Leongatha, Victoria, in July 2023.

Heather’s husband, Ian Wilkinson, 69, was hospitalised for several months after the lunch, but survived.

Simon was invited to the lunch but pulled out the day before.

Patterson will be sentenced later this year.