But Ms Day's family argue the force is trying to skirt its responsibility and remain optimistic coroner Caitlin English won't let them do so.

The 55-year-old grandmother fell and suffered a head injury while in a regional Victorian police cell after being arrested for drunkenness on a train on December 5, 2017.

She died two weeks later.

In a final written submission to an inquest into the death, Ms Day's family argued it is "possible" police committed offences which coroner Caitlin English should refer to the Department of Public Prosecutions.

They also want the coroner to acknowledge systemic racism and unconscious bias were central to Ms Day's death, because public drunkenness laws were more likely to be applied to her as an Aboriginal woman.

The family further want the coroner to recommend police should not have the opportunity to investigate other police.

"There is no doubt in our mind that Victoria Police are responsible for our mum's death," Ms Day's daughter Belinda Day told reporters in Melbourne on Monday.

Lawyer for the chief commissioner of Victoria Police Graham Ashton, Rachel Ellyard, says the submission reflects the family's "feelings" and "deep distress" over the death.

She urged the coroner to act upon the evidence she heard during the inquest when making her assessment and not such "reflections".

"Your Honour ought not be influenced by what I'll call the opinions of interested parties," she told the court during final oral submissions.

Ms Ellyard said the inquest heard no evidence that police had broken the law by being negligent in how they treated Ms Day.

"The evidence isn't there. If it were, Your Honour would long since have made the referral."

She also dismissed the suggestion police involved in Ms Day's situation had been driven by racism.

"There was no inappropriate regard, consciously or unconsciously, to her (Ms Day's) Aboriginality," she said.

In its written submission, Victoria Police's chief commissioner's office said police had properly followed laws and guidelines or explained when they hadn't done so.

Lawyer for Ms Day's family Peter Morrissey said on the contrary, the inquest had shown police had fallen short by not noticing when Ms Day has fallen.

"They cannot have been adequately monitoring her," he told the court.

Ms Day's son Warren Day said Victoria Police's final submissions show the force wants to learn nothing from his mother's death.

"All we saw was an attempt to normalise the behaviour of police and an attempt to get out of all responsibility," he told reporters after the hearing.

"Without accountability, more Aboriginal people will die in custody."

The coroner is expecting to hand down her findings in March.

EARLIER: The children of Yorta Yorta woman Tanya Day will urge the Victorian coroner to refer individual police officers to the Director of Public Prosecutions for criminal investigation in relation to her death.

Ms Day's family will also call on the coroner to find that systemic racism and unconscious bias was a cause of their mother's death in custody, in their final submission to be tendered to coroner Caitlin English in court on Monday.

"These issues are almost never talked about in inquests and other court proceedings. But they played a central role in our mum's death," Ms Day's children say in their final submission.

"You cannot properly make findings about what has happened without considering them."

They will ask Ms English to recommend police should not investigate allegations against other police officers.

"It is clear to us that the investigation into our mum's death has been flawed and inadequate. This is because police should not be investigating police. What we now want is a criminal investigation," say the Day family.

READ MORE: FOLLOW THE 14-DAY TANYA DAY TRIAL HERE

Their powerful statement conveys the distress their mother experienced when she was taken into custody.

"They took me to the divvy van. I had the most terrible, sinking feeling. I knew what was going to happen now. Like my uncle Harrison, like so many of my people, I was going to be locked up in a police cell when I had done nothing wrong," says the statement.

Ms Day died in December 2017, aged 55, after she was arrested for public drunkenness while travelling to Melbourne on a V/Line train and taken into custody in Castlemaine.

Ruth Barson, legal director at the Human Rights Law Centre, who is representing the family, said accountability is critical to prevent future deaths in custody.

"No police officer has ever been held criminally responsible for an Aboriginal person's death in custody, despite hundreds of Aboriginal people dying in their care," Ms Barson said.

Ms Day's inquest was told police officers detained the Aboriginal woman for four hours to "sober up" after she was arrested for public drunkenness, despite this approach not being part of official police guidelines.

Police also did not comply with their own guidelines for checking detainees because they were short-staffed on the night she was in custody, the inquest heard.

Leading Senior Constable Danny Wolters said a lack of staff was one of the reasons he twice left more than 40 minutes between checking on the Yorta Yorta woman, despite police guidelines requiring that an intoxicated person must be physically checked and roused every 30 minutes.

Leading Senior Constable Wolter later told the court his verbal checks on Ms Day were probably "50 per cent inadequate".

The Andrews government has announced public drunkenness would no longer be a crime in Victoria, in a law reform that seeks to redefine alcohol abuse as a health issue.

-The Age

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