Hearing on accused Bourke St driver begins

Accused Bourke Street driver Dimitrious "Jimmy" Gargasoulas has walked into a court for the first time since he was charged over a Melbourne rampage that killed six people in 2017.

The 28-year-old appeared in person before the Victorian Supreme Court on Tuesday for day one of an investigation hearing about his fitness to stand trial.

It marks the first time Gargasoulas has sat in the dock since six people were killed when a car ploughed into pedestrians at Bourke St mall on January 20, 2017.

He has appeared via video link at his previous court dates.

Gargasoulas faces six counts of murder and 28 charges of attempted murder over the rampage, as well as other, unrelated charges.

A jury of 12 people has been selected to hear specialist medical evidence about whether Gargasoulas is mentally fit to stand trial.

"Ultimately it's your opinions that matter," defence barrister Theo Alexander said.

Dr Alexander said the defence requested the hearing because of concerns about Gargasoulas' mental state.

"We ask, and you assure, that you will apply your mind to the question impartially and objectively, not withstanding the terrible and overwhelmingly sad circumstances," he told the jury.

The barrister said accused people are presumed to be fit for trial unless a jury determines a person is not fit "on the balance of probabilities".

"The defence must establish to your satisfaction that he is more likely than not unfit," Dr Alexander said.

"Mental illness is not of itself sufficient to say that someone is not fit for trial."

In his opening address, prosecutor Andrew Tinney SC said Gargasoulas has schizophrenia.

"The accused is fit to stand trial despite his illness," he told the jury.

Mr Tinney said defence and prosecution experts agree Gargasoulas is schizophrenic.

"Two of the psychiatrists will express the opinion that as a result of the serious illness from which the accused suffers - schizophrenia - he is not fit.

"But you'll also hear evidence from another highly-trained specialist, a professor in psychology, and his evidence will indicate that the accused is fit."

The hearing before Justice Lex Lasry will resume on Wednesday.