The police strategy to try and stop James Gargasoulas murdering six people and injuring 27 others along Melbourne's Bourke St Mall was never going to work, the coroner said.
That's the finding of coroner Jacqui Hawkins into the horrific rampage that "struck at the heart of Melbourne" on the afternoon of 20 January 2017.
Three-month-old Zachary Bryant and 10-year-old Thalia Hakin were among those killed when Gargasoulas drove a stolen car through CBD lunchtime crowds.
Jess Mudie, 22, Yosuke Kanno, 25, and 33-year-olds Matthew Si and Bhavita Patel also died.
Ms Hawkins on Thursday detailed a litany of police failures that meant "such a violent, drug-fuelled, psychotic and delusional perpetrator was able to slip through the cracks".
"The negotiated surrender plan really amounted to nothing more than two phone calls and a series of bizarre text messages," she said in her findings handed down in Victoria's Coroners Court.
"There was no actual negotiation. There were no plans made, nor agreement reached. The strategy never had a chance of succeeding."
Gargasoulas was released from custody by a bail justice during an after-hours hearing six days before the rampage.
Ms Hawkins made nine recommendations, including improving training so police could better identify grounds on which they might be able to oppose bail.
She also called for the force to look at the potential use of police body-worn cameras in out-of-sessions bail and remand hearings.
The coroner did not mention the killer's name during her findings out of respect for the victims' families.
Thousands attend a vigil for the Bourke Street victims at Federation Square in Melbourne, 23 January 2017. Source: AAP
"To simply describe these events does not capture their horror, occurring as they did in the midst of crowds of shoppers, tourists and office workers enjoying the height of summer," she said.
"Numerous witnesses likened it to a nightmare. The moments they witnessed were simply beyond their comprehension.
"The offender's actions are both unthinkable and repellent. They struck at the heart of Melbourne."
Gargasoulas has been jailed for life, with a non-parole period of 46 years, for what the sentencing judge described as one of Australia's worst examples of mass murder.
