There is insufficient evidence to prove a sailor who confessed to killing three people is responsible for the death of a woman he met at a bar in Western Australia almost 20 years ago, a coroner has found.
Sara-Lee Davey, 21, went missing in January 1997 after going to the Broome Wharf with 19-year-old Richard Dorrough, who was a Royal Australian Navy sailor on shore leave from HMAS Geelong.
Police interviewed Dorrough but never charged him over Ms Davey's disappearance.
He was later charged, following a cold case review, with the 1998 murder of 29-year-old prostitute Rachael Campbell in Sydney, but was acquitted at trial in 2010.
Dorrough was 37 when he took his own life in August 2014 and left a letter saying he had killed three people, prompting police to review Ms Davey's case and infer he was responsible for her death.
An inquest earlier this year heard Dorrough tried to bring Ms Davey aboard HMAS Geelong, but was stopped by Able Seaman Dean Mildenhall.
Dorrough told his colleague he was going to take Ms Davey to the end of the wharf to have sex with her.
Several people were fishing off the jetty and one fisherman said he heard a woman yelling and screaming, followed by a splash.
Dorrough returned to HMAS Geelong a short time later with scratch marks on his face.
He told his colleague Ms Davey would not have sex with him and had left, but Mr Mildenhall never saw her leave the wharf, the inquest heard.
Coroner Barry King said in his findings on Wednesday he was satisfied there was a violent confrontation between Dorrough and Ms Davey.
"There is a undoubtedly a strong inference that can be drawn from the evidence that Mr Dorrough killed the deceased on the wharf and threw her body into the ocean where she was carried out to sea by the tide." he said.
But Mr King said there was also the possibility she fell from the wharf and was unable to swim to land.
"That possibility is made more realistic by evidence that the deceased appeared quite intoxicated while at the Nippon Inn," he said.
Mr King said Ms Davey's death had been proved beyond reasonable doubt, but the cause was unascertained and he had to make an open finding.
"I am unable to determine to the required level of satisfaction whether Mr Dorrough caused the deceased's death," he said.
Mr King said the case could be reconsidered if further evidence became available.
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