A Newcastle woman whose naked body was found in a Blue Mountains dam might have gone into the water on a "walkabout" while suffering a mental health episode, an inquest has heard.
Cecilia Devine, 42, was found dead on March 18, 2019, in the remote Upper Cascade Creek dam catchment at North Katoomba. She was last being seen in the nearby NSW village of Katoomba more than six months earlier, on September 6, 2018.
The inquest in Sydney on Friday examined the manner and cause of the musician's death, which remains a mystery.
Detective Sergeant James Allan, the officer in charge of the investigation, told the inquest a likely hypothesis was that Ms Devine, who had bipolar disorder, walked into the dense bushland, entered the dam and passed away in a case of misadventure.
On the day she was last seen alive, she had been travelling for about 17 hours without shoes and had previously gone on "walkabouts" during which she would dispose of her possessions.
Ms Devine could sometimes go walkabout for around 24 hours before turning up to hospital or calling an ambulance, the inquest heard.
Det Sgt Allan said suicide was unlikely, but homicide could not be excluded.
Police looked into several persons of interest, but all were eliminated as potential murder suspects.
Asked for his opinion on why Ms Devine's body was found naked, Det Sgt Allan said it was possible she took her clothes off due to the effects of hypothermia before she entered the water.
Quizzed on the police investigation, the detective stood by evidence that Ms Devine could be "drawn to water" during recovery from a mental health episode.
Several witnesses told police Ms Devine was a modest person who did not take off her clothes in public and even swam clothed in her friend's backyard pool.
Det Sgt Allan conceded the "objective likelihood" of a 3km walk to the dam from Coles at Katoomba, where Ms Devine bought groceries on the afternoon she vanished, was low.
"(But) it's still a plausible hypothesis as to what happened to Cecilia," he said.
Ms Devine was reported missing on September 5, 2018, from Waratah, a suburb in Newcastle, after family and friends were unable to find or contact her, investigators have previously said.
Police launched a murder investigation into her death in May 2019 and have said they are confident that there are people in the community who have information about the case.
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