Alex Reuben McEwan is not mentally fit to continue to stand trial for the murder of Korean woman Eunji Ban, a Supreme Court jury in Brisbane has decided.
Mr McEwan was charged with murdering Ms Ban in Brisbane's Wickham Park in November 2013.
It took jurors four hours to come to the unanimous decision that the 23-year-old could not continue the trial.
He has admitted to killing the young Korean woman but denied it was murder.
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He was planning to use insanity as a defence.
Mr McEwan will now be transferred to a mental health facility.
His fate in relation to the trial will be determined at a later date.
Outside court after the decision, relatives of both the victim and the accused declined to comment.
The trial has been halted twice because of Mr McEwan's current state of mind and health.
Jurors were told they would need to decide whether he is mentally fit to continue the trial, but it would not be a determination on the murder charge.
Forensic psychiatrist Dr Donald Grant told the court that Mr McEwan was instructed by demons in his head to attack the prosecutor in the trial on Tuesday and his hallucinations have increased since the start of the trial.
Prosecutor David Meredith had told jurors he "wants to see matters resolved as promptly as possible" and that prosecution could continue after Mr McEwan received treatment.
"Your decision does not determine his guilt or innocence," he said.
"The prosecution can continue at a later time."
Defence barrister John Allen told the jury they should accept Dr Grant's evidence that Mr McEwan was not fit for trial because of psychotic hallucinations.
"The defendant is just not able to properly appear, understand and pay attention to evidence, and therefore be able to give sensible instructions to his lawyers," Mr Allen said.
"If he is to defend the charge against him he will be required to give evidence — he simply cannot have a fair trial."