Carly Pirronelli, 26, was shot dead on March 8, 2024, after police were called to her mother Joanne Perry's home in Melbourne's northeast.
A neighbour had raised the alarm after hearing the 53-year-old woman yelling for help and saying "please don't kill me, don't set me alight".
Two officers arrived at the Lower Plenty property about 6.40pm and found Carly leaning over her mother, surrounded by a significant amount of blood.
They ordered Carly to drop the large knife she was using to cut into her mother's neck but she continued her attack.
One of the officers then fired eight shots at Carly within 21 seconds.
She slumped forward and although paramedics were called, both women died at the scene.
The circumstances of their deaths and Carly's behaviour in the lead-up will be investigated in an inquest, which started at the Victorian Coroners Court on Monday.
Carly's mental health had declined in the months prior and she had multiple interactions with police and the hospital system, counsel assisting Raph Ajzensztat told the court.
This included an incident on February 20 when Carly had to be restrained by paramedics and taken to hospital after suffering a drug-induced psychosis.
She was also accused of stealing a Toyota Hilux on March 1 and evading police on other occasions.
Joanne also made reports in relation to her daughter, including on February 18 when she told a triple zero call-taker that Carly had attempted to strangle her.
The 53-year-old also wanted her daughter taken to hospital on March 7, telling officers Carly was acting erratically and saying she wanted to kill herself.
The officers and paramedics who encountered Carly and Joanne in the lead-up to their deaths will be among the witnesses to give evidence during the inquest.
The officer who fired the fatal shots will also be called, alongside forensic and psychiatric experts.
The inquest before deputy state coroner Paresa Spanos is expected to run for two weeks.
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