A Melbourne jury is struggling to come to a unanimous decision on whether Bourke Street driver James Gargasoulas is mentally fit to stand trial for murder.
Gargasoulas, 28, is accused of running down pedestrians in the city in January 2017, killing six people, including two children, and injuring many others.
He is facing an investigative Supreme Court hearing to decide if he is fit to face trial on six counts of murder and 28 of attempted murder.
A jury of 12 retired to consider their verdict on Monday, but on Tuesday afternoon sought guidance from Justice Lex Lasry, saying they were torn.
"I have been informed that you have not been able to reach a decision," the judge said.
Justice Lasry said he could dismiss the jury without a verdict if they could not reach one but he was not yet ready to do so.
"Experience has shown that juries, given more time to discuss, can reach a verdict," he said.
"That's what I'm going to ask you to do. Come back in the morning, hopefully fresh."
Justice Lasry urged the jury to share their feelings and listen to others, as their views may shift.
But he said they can't change their minds simply for the sake of reaching a decision.
"To do that would breach your duty to the court," he said.
Medical experts in the case have been divided over the question of Gargasoulas's fitness.
Two psychiatrists believe he is unfit for trial but one psychologist disagrees.
The defence argues he is "profoundly psychotic", believing he is the "Messiah" sent to save the world from a comet, and should not stand trial.
But prosecutors say Gargasoulas should face trial, claiming he understands his case and can make decisions about his defence and plea.
"(He) has the presence of mind to know that if it's his lot in life to be saving the world, he wants to be doing that from the relative comfort of Thomas Embling Hospital, rather than the 23-hour lockdown of prison,' crown prosecutor Andrew Tinney SC said.
The jury will continue deliberations on Wednesday.
Australian Associated Press