A dedicated veteran Tasmanian police officer who took his own life feared his post-traumatic stress disorder diagnosis would prevent him from returning to work.
An inquest is examining the October 2020 death of Sergeant Robert Anthony Cooke, 49, as well as the suicides of three other police officers in separate incidents.
Sgt Cooke, whose career began in 1990, was formally diagnosed with PTSD in June 2019 after going onto worker's compensation earlier in the year.
"(An) expert medical report ... refers to a cumulative exposure to traumatic situations, together with overwork and sleep deprivation as being causative factors," counsel assisting the coroner, Cameron Lee, said during an opening submission on Thursday.
The medical report said Sgt Cooke, who was described as beloved by his colleagues, could participate in a return-to-work program.
The inquest was told he did so in a police radio role but there were difficulties with training, making it short-lived.
The inquest, which will run over several weeks, will examine the impact of return-to-work programs on Sgt Cooke's mental health.
It will also examine staffing movements surrounding Sgt Cooke's desire to return to work at Oatlands police station and his concerns he wouldn't be able to.
The inquest was told a new role was created at Oatlands to preserve Sgt Cooke's position for when he was fit to return.
In May 2020, Sgt Cooke told a colleague he was worried his PTSD diagnosis would preclude him from ever returning to work and he was finding it hard to walk away, the inquest was told.
The day before he died, Sgt Cooke told his sister "he would kill to be at work".
Mr Lee described Sgt Cooke, a father of two, as someone who was generous with his time and highly supportive of his colleagues.
He also held a senior role with the Police Association of Tasmania.
"It seems that he just loved being a frontline policeman," Mr Lee said.
The inquest was told Sgt Cooke had been working 60-hour weeks with little downtime, plus the requirement of being on-call when not on duty.
The inquest is also examining the deaths of Constable Paul Hunt, Senior Sergeant Paul Reynolds and Constable Simon Darke.
It is investigating policy and procedures of Tasmania Police in respect to the standing down, suspension and termination of officers, as well as the organisation's welfare and fatigue-management programs.
Mr Lee said a colleague would provide evidence that Const Darke had "run out of fight" amid conflict with his partner and had ongoing scars from failed previous relationships.
He was also working in an isolating policing role, Mr Lee said.
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