The Northern Territory police force has been repeatedly criticised as incompetent by a coroner over its failed investigation into the alleged murder of Aboriginal woman Sasha Kwementyaye Green.

However, the NT coroner Greg Cavanagh stopped short of blaming racism for the botched inquiry, an accusation levelled by Green’s parents.



Green, 25, was found lying dead next to her sleeping partner Rodney Shannon, surrounded by a puddle of water under an unzipped sleeping bag in Tennant Creek on 22 November 2013.



She had been stabbed in the thigh, resulting in a severed artery.



However, after the arrest of the prime suspect Shannon on the day of the death, he was released hours later before the police had forensically examined all the evidence, including a unit the couple had been in.

He remained the prime suspect nearly five years later, the police assistant commissioner Michael Murphy said on Thursday.

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A unit the couple had been in that night was not examined for another five days and evidence was destroyed by police, which the coroner described as outrageous and called for action to stop that happening.

The case was not declared a major crime at the time as it should have been to command enough resources and supervision, and the police took more than two years to meet the coroner’s October 2015 request for an investigation file.



They developed an “irrational preoccupation” that Green had killed herself, despite there being no history of self-harm.



The police sent inexperienced investigators, one on his first day with the Major Crime Squad.



“There is no doubt that incompetent management of this case from all levels contributed to the very poor outcome,” Cavanagh said.



“It was so poor that prosecution would only have been possible if the killer confessed.”



The coroner did not accept the view of the lawyer of Green’s family, John Lawrence, that institutional racism had driven the NT police actions, given that successful investigations of recent murders of white women had taken place.



But nor did he rule it out.



Murphy apologised in person to Green’s father, Casper, for mistakes he conceded had been made and offered his condolences.



He said the police had made improvements to training in relation to investigations.

