A Tasmanian police officer who took his own life was worried about being judged if he sought help for his mental health, his former partner has told an inquest.
The death of Constable Robert Darke in 2019 is one of four police officer suicides being examined at an inquest which is investigating Tasmania Police policies and procedures.
His ex-partner Shanna Sweeney said she disclosed to police in 2011 that Const Darke had threatened to take his own life.
Ms Sweeney told the inquest she made the disclosure to a police officer but she didn't "remember him saying much" in reply.
"But I was shaken at the time and really nervous about phoning the police," she said.
Ms Sweeney believed it was "common knowledge" among local police that Const Darke had threatened self-harm, even though he denied it.
She said Const Darke had made earlier comments to her about self-harm, but she didn't report them to his workplace.
"I didn't want Simon to be in trouble at work. There was a thought that if he was seen as being vulnerable ... he'd be punished. I wanted to get him help," Ms Sweeney said.
The inquest was previously told Const Darke, 45, left a night shift at a Hobart police station and was found dead in the early hours of the next day at a Midway Point home.
Ms Sweeney said Const Darke, who she started seeing in 2004, liked his job but had struggled during their separation and showed a "very strong pattern of emotional instability" when they were together.
"I knew he was serious about suicide at some stage in his life. Once we separated it was almost like a train colliding," she said.
Ms Sweeney described Const Darke as a closed book when it came to talking about his work.
"(There) was a perception of being judged if he got help," she added.
The inquest continues.
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