The absence of a fatigue management policy in Tasmania Police played a direct role in a sergeant's death, a coroner has found.
Sergeant Robert Cooke was one of four male officers who took their own lives between 2016 and 2020, along with Senior Sergeant Paul Reynolds, Constable Paul Hunt and Constable Simon Darke.
An inquest into their deaths examined police processes in relation to issues including fatigue, welfare programs and complaint investigations.
Sgt Cooke, who joined the police force in 1990, had severe post-traumatic stress disorder (PTSD) and was off work when he died in October 2020, aged 49.
He had earlier been "tired, frustrated and suffering difficulties" with the workload at a busy rural station.
Sgt Cooke attended numerous critical incidents during his career and suffered a "final straw" working long hours battling bushfires in 2019.
Coroner Simon Cooper said Sgt Cooke's PTSD, diagnosed in May 2019, was cumulative and probably stretched back to 1994.
Mr Cooper said Tasmania Police had no fatigue management policy in place as recently as when the inquest was held at the end of 2022.
"The absence of any fatigue management policy was, I consider, a direct factor in Sergeant Cooke's death," he said in findings released on Friday.
Mr Cooper said Sgt Cooke's PTSD was treated appropriately but wasn't diagnosed until it was chronically entrenched.
"His case illustrates the need for early diagnosis of the condition," he said.
Mr Cooper said it was essential the issue of fatigue management was addressed and a policy was implemented.
He called on Tasmania Police to conduct mandatory six-monthly screenings of all operational police officers for PTSD.
Police Commissioner Donna Adams said her thoughts were with the friends and families of the four men and all findings would be considered in detail.
She said Tasmania Police was rolling out a fatigue management framework on a trial basis for six months and a nation-leading six-day-off, six-day-on roster was also being trialled.
Mr Cooper also recommended several changes to wellbeing support processes for officers being investigated by police professional standards.
Const Hunt, who died on July 8, 2016, didn't have access to support he needed after being served with a stand down notice that day.
He was being investigated by police professional standards for potentially engaging in criminal activity amid a lengthy history of abuse of over-the-counter drugs and driving under the influence.
Const Hunt was required to hand over his mobile telephone and was unable to be contacted by anyone concerned for his welfare.
Sen Sgt Reynolds was being investigated over serious child exploitation allegations when he died, aged 54, in September 2018.
He had his house searched by police professional standards officers the night before his death over accusations he had groomed and sent inappropriate images to young boys.
Mr Cooper said the fact Sen Sgt Reynolds was not provided with a replacement mobile phone, to access welfare support, when his was seized was contrary to guidelines.
However, Mr Cooper said that factor didn't play a role in Sen Sgt Reynolds' death.
Mr Cooper said Const Darke was experiencing a difficult relationship break-up and no one had any inkling he intended to take his own life.
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