But Elliott said “the misleading information caused by AI did not end there” and the revised documents referred to made-up laws.

“Revised submissions were not reviewed by either side … and referred to legislation that did not exist, an act that was repealed that never occurred,” the judge said.

Defence apologised again and eventually filed their documents without AI inaccuracies.

“The manner in which these events have unfolded is unsatisfactory,” Elliott said.

He said the ability of the court to rely on submissions was “fundamental to the administration of justice” and all litigants should adhere to the Supreme Court’s guidelines on AI.

“Use of AI without careful oversight of counsel would seriously undermine this court’s ability to deliver justice,” he said.

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The guidelines state use of AI must not “directly mislead another participant in the litigation process as to the nature of any work undertaken or the content produced by that program”.

Nathwani offered his “genuine and sincere apologies” to the judge and said he was embarrassed by what had occurred.

Prosecutor Daniel Porceddu also apologised and admitted he did not read the defence’s references and citations.

He did not further verify the documents’ contents because he agreed with the conclusion reached in the defence submissions, he said.

The boy, who sat in court as the issue was raised, has been directed to remain under supervision at a Youth Justice Centre following the mental impairment finding.

He was accused, on the basis of complicity, of agreeing to commit the murder with a co-accused in order to steal the woman’s car, drive to the Grampians, blow up a bridge and build an anti-communist child army to take over Australia.

The plan was never enacted, and he was arrested after the killing near Ballarat.

He was found to be mentally impaired during the offending as his schizophrenia was untreated at the time and he followed “grandiose delusions” that he was a prophet of God.

Elliott noted, unlike in NSW, there are no adolescent psychiatric units in Victoria that he could be taken to.

He said the boy would continue to receive anti-psychotic treatment for his schizophrenia in youth justice.

The boy will return to court for a supervision hearing on November 5.

AAP

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