The daughter of a gunman who murdered two women in one of Western Australia's most horrific cases of family violence has delivered a powerful apology at the inquest into their deaths, condemning him as a "powerful, privileged entitled man" intent on control and revenge.
WARNING: This story contains details that may distress some readers.
Jennifer Petelczyc, 59, and her daughter Gretl, 18, were killed by Mark Bombara as he stormed their home in the Perth suburb of Floreat in May 2024, in pursuit of his estranged wife, Rowena.
Bombara then turned the gun on himself.
His daughter Ariel told the inquest her father was a "devious, ruthless manipulator" who when he could not find his wife, decided murdering her best friend "would be the next best punishment".
"I am so sorry that some feel the need to excuse his behaviour as medical or mental health issues, as opposed to acknowledging that these were planned choices he made to murder," Ariel Bombara told the court.
"Killing her [Rowena Bombara] was the only thing that would have truly satisfied him.
Jennifer and Gretl Petelczyc were shot dead by Mark Bombara at their Floreat home. ( Supplied )
"Make no mistake; he viewed her as his property and, [medical] strokes or not, in my opinion, he never would've let mum leave him without a death penalty."
Ms Bombara addressed Liesl Petelczyc, Jennifer's daughter and Gretl's sister, who was sitting in the public gallery.
Liesl was out at a babysitting job when Bombara stormed her family home.
"Your mum and sister did not deserve to be killed," she said.
"I am so sorry, Liesl, that so many people let you and your family down."
Ariel Bombara tried to warn police at least four times that her father was a real and imminent threat and had access to firearms, when she helped her mum escape the family home, weeks before the murders.
The inquest continues into the Floreat murder-suicide. ( ABC News: Ruby Littler )
Appropriate action was not taken, according to an internal police investigation, and eight officers have since faced disciplinary action.
"I would do anything to go back and scream "fit and proper" into the faces of a hundred police officers, hoping that one would finally believe us; help us; and take his lethal weapons away," Ms Bombara said.
Ariel Bombara says her father was a "devious, ruthless manipulator". ( ABC News: Lucy Murray )
"I have thought about these events every single day for the last two and a half years, wondering what more I could've done to convince everyone of the danger, and knowing that for the rest of my life I will feel like I pulled the pin on the grenade that landed on someone else's family.
"I am so sorry to my mum for not being able to protect her from him better … I am so sorry that she had to hear her best friend be murdered by her abusive husband over the phone.
"Her scream after hearing those shots, and her wails long after that Triple Zero call ended, are sounds that will haunt me for the rest of my life."
Speaking publicly for the first time since the murders, Rowena Bombara told the court she was heartbroken at the loss of her best friend Jennifer Petelczyc, and Jennifer's daughter Gretl.
She said Gretl "had a wonderful sense of humour and her whole life ahead of her".
She also spoke of her fear of her husband.
"I knew what would happen if Mark found me," she said.
"That's why I deliberately never stayed with Jenny in her home.
The court has issued suppression orders preventing media outlets publishing images of Rowena Bombara and Liesl Petelczyc.
Floreat double-murderer Mark Bombara. ( Supplied )
Acting state coroner Sarah Linton said there was "not a dry eye" in the room at the conclusion of her statement, adding she did not have "the words to express her sorrow" for the families involved.
The findings are expected to be handed down next year.