The daughter of a Yorta Yorta woman who died in a police cell in Castlemaine in 2017 after being arrested for public drunkenness has testified to the Victorian Coroner’s Court that she believed her mother would have been treated differently by authorities if she was white.

Coroner Caitlin English is considering whether to examine if systemic racism played a role in the death of Tanya Day.

Ms Day’s daughter, Apryl Watson, also said in her submission to the court yesterday that her mother “didn’t deserve to be treated like she was nothing”.

Tanya Day, 55, was en route to visit her children in Melbourne when she was arrested on a V/Line service from Echuca on December 5, 2017. She was taken to Castlemaine Police Station, where her family say CCTV footage shows that she hit her head on four occasions.

She was not monitored every half hour, as required by police guidelines, and was eventually rushed to Bendigo Hospital, where scans revealed a bleed on her brain. She died at St Vincent’s Hospital in Melbourne 17 days later.

Coroner Caitlin English will make a final decision on the scope of the inquest, which is set to take place from September 10th to 13th, within four weeks.

Acting for the family, Emrys Nekvapil told the court that systemic racism – which he says is “unwitting, unconscious racism” – is hard to see because we’re often looking for the wrong thing.

“It’s a thing that is deadly, and all the more deadly because it is almost invisible to the people it doesn’t kill,” he said.

He cited data obtained by the Humans Rights Legal Centre, which shows that Aboriginal and Torres Strait Islander women are 10 times more likely to be targeted by police for public drunkenness than non-Aboriginal women.

Belinda Stevens, Ms Day’s eldest daughter, said the statistics are “appalling”, but stressed that her mother is not just another statistic.

“She’s our mum. She’s no longer with us, and she no longer gets to spend time with her children, her grandchildren, and contribute to society and to her community.”

“Let us be the last family to experience this grief of losing a loved one in these circumstances.”

Mr Nekvapil told the court that “we are not asking you to engage in a royal commission into the systemic factors that lead to that disproportion”. Instead, he said, “the inquiry needs to go beyond direct physical cause of death”, and must assess how unconscious racism might have contributed to the treatment Ms Day received from V/Line staff, ambulance officers, and police.

The inclusion of systemic racism in the scope of the inquest, he said, would help others to see what Tanya Day’s family see.

But Victoria Police’s lawyer, Rachael Ellyard, said that Ms Day’s case wasn’t suitable for an analysis of the role of systemic racism.

“The focus is on what happened to Tanya, as opposed to whether Tanya is representative of a broader class. You can do that without the frame of systemic racism,” she said.

The Victorian Equal Opportunity and Human Rights Commission (VEOHR) joined the family in asking the coroner to consider whether systemic racism played a role in Ms Day’s death. Acting for VEOHR, Kylie Evans argued that the Coroners Court is a public authority under the Victorian Charter of Human Rights and Responsibilities, and therefore is bound by it.

The VEOHR argues that Coroner English’s decision could have broad implications for how the charter is applied in coronial inquests.

Ms Evans also said that “there is an allegation that she (Ms Day) was treated in a particular way on the basis of her race, and that is sufficient for engagement of charter rights”.

At the first directions hearing into Ms Day’s death in December, Coroner English stated her intention to recommend to Attorney-General Jill Hennessy that the law of public drunkenness be abolished. Victoria and Queensland are the only states that still have such legislation. The abolition of public drunkenness laws was a key recommendation of the Royal Commission into Aboriginal Deaths in Custody, and several inquiries since.

Belinda Stevens said that although the family has had preliminary discussions with government representatives, and over 7000 people have signed an online petition asking for the law to be changed, she’s not expecting the law to be repealed before the inquest is completed.

“We’re hopeful, but certainly not expecting anything.”

Jack Banister was a part of Guardian Australia’s Deaths Inside investigative team, which revealed that more than 400 Aboriginal and Torres Strait Islander people have died in custody since the end of the royal commission into Aboriginal deaths in custody in 1991.