Tianna Addison Diodato Day: Alleged Karrakatta firebug also accused of Mandurah cemetery arson

A 28-year-old woman accused of destroying the main chapel at WA’s biggest cemetery allegedly committed arson just days earlier at a cemetery closer to her home. Tianna Addison Diodato Day was arrested after a blaze gutted Karrakatta Cemetery’s Norfolk Chapel late on Tuesday night, causing an estimated $1 million worth of damage. She faced Perth Magistrates Court on Wednesday from behind a secure screen, wearing a pink fluffy dressing gown and a dazed expression. The court was told that Ms Diodato Day had also set fire to a shed at Lakes Lawn Cemetery in Parklands, north-east of Mandurah, about 3.30am on September 27. Grave-digging and gardening equipment including a backhoe loader and ride-on mower were destroyed, along with the shed itself. Police say she took images of the flames on her mobile phone then went back three days later and set fire to a small office building at the cemetery. The court was told she picked up a metal sign at Karrakatta Cemetery and used it to smash a window to get inside the building, then poured an accelerant from a jerry can. The adjacent condolence lounge was also badly damaged in the blaze. The case against Ms Diodato Day already appeared strong, the police prosecutor said, with evidence including the incriminating images on her phone and CCTV footage from Karrakatta. Her car’s licence plates were also picked up on Kwinana Freeway cameras going from her Mandurah home to the western suburbs cemetery and back again around the time of the offence. “A lengthy term of imprisonment is almost inevitable,” he said. “We don’t know why she’s done this.” Her lawyer said she had an unfair dismissal case underway after losing her job as a receptionist in March — a position she’d held since 2019 and taken great pride in. “People lose their jobs all the time. It doesn’t mean they go out and burn stuff,” Magistrate Andrew Matthews said. He noted how far she had allegedly driven to commit the Karrakatta arson. “There’s no rational explanation for any of this offending,” the magistrate said. The lawyer said her client had mental health issues, but her offending was “extremely out-of-character”. She proposed her being ordered to stay home around the clock if necessary — and not go near any cemeteries — as bail conditions. But the prosecutor firmly opposed bail, saying police feared she could cause “further catastrophic property damage or worse still, harm to individuals”. Mr Matthews agreed that protecting the community was paramount and remanded Ms Diodato Day in custody, ordering a home detention bail report before her next court appearance on October 16.