Melbourne's Bourke Street killer James Gargasoulas has been jailed for life for committing one of Australia's "worst examples of mass murder".

The 29-year-old was emotionless as he was sentenced to spend at least 46 years in jail for his deadly driving crimes in Victoria's Supreme Court on Friday.

In one of the city's darkest days, Gargasoulas used a stolen car to mow down and kill six people on the busy Bourke Street mall on January 20, 2017.

0:00 James Gargasoulas found guilty of six murders 00:00 / 00:00 Share Share on Twitter

Share on Facebook

Justice Mark Weinberg sentenced Gargasoulas to life in prison for each of the six counts of murder. The non-parole period has been set at 46 years.

"I do not accept that you are genuinely remorseful," the judge said.

Justice Weinberg said earlier in his sentencing remarks that Gargasoulas was suffering from a drug-induced psychosis and not a mental illness at the time of the attack.

AAP

"Whatever your state was during the offending - you are now genuinely psychotic. Your condition is not likely to improve in the foreseeable future. It is likely to worsen."

Gargasoulas' victims included three-month-old baby Zachary Bryant, who was thrown 60 metres from his pram, and 10-year-old girl Tahlia Hakin.

Gargasoulas injured dozens of others, knocking them to the ground and into walls while driving in a drug-induced psychosis.

Family of victims in court

Family of the victims filled the courtroom for Justice Mark Weinberg's ruling, which comes more than two years after the massacre.

"This was one of the worst examples of mass murder in Australian history," Justice Weinberg said.

AAP

"The horror of what you did has profoundly impacted the lives of those who were present that day," Justice Weinberg said, noting in detail the events of the "terrifying rampage" which included caused death, broken bones, head injuries and other serious damage.

Grieving relatives recently told the court of their pain, with the brother of Japanese victim Yosuke Kanno saying he will "continue suffering from this until I die".

Robyn Davis, the mother of victim Jess Mudie, said her daughter died three weeks before her 23rd birthday.

"Never in my wildest nightmares did I think I would have to bury one of my precious children," she told a plea hearing in January.

In a joint statement, the family of five victims said dangerous murderers like Gargasoulas "should never be allowed to roam freely".

"The sentence is not harsh enough," the families of five victims said in a joint statement.

"Our family hopes that no one will ever have to suffer a similar fate as those who lost their loved ones."

Gargasoulas blames 'government oppression' for the murders

In a letter read to the court, Gargasoulas insisted he was not evil and blamed "government oppression" for the murders.

He also maintained he was the Messiah and acted on the wishes of God on the day of the rampage, but said he was in a "bad headspace".

Gargasoulas pleaded not guilty to killing Zachary, Thalia, Ms Mudie, Mr Kanno, 25, Matthew Si, 33, and Bhavita Patel, 33.

Supplied

But in November it took a jury less than an hour to unanimously find him guilty of the six murders and 27 counts of reckless conduct endangering life.

An earlier jury found Gargasoulas, who suffers treatment-resistant paranoid schizophrenia, was fit to stand trial.