And shocked staff left the man's body unsupervised for long stretches, allowing it to be interfered with, while the suspected killer was left free to roam the ward and assault other residents.

Former pharmacist Charles McCulloch, 94, moved into the secure dementia ward of Narrabundah's Jindalee Aged Care Residence on 20 January, 2012, after being transferred back and forth between two facilities in NSW.

One day later, he was dead, staff pulling back his bed covers to find him bloody and with significant facial injuries.

An inquest began exploring the circumstances of his death on Monday, and will scrutinise whether there are systemic issues with Jindalee's handling and supervision of high-needs dementia patients.

Counsel assisting Amanda Tonkin said the inquest is likely to explore whether CCTV cameras should be installed in the dementia ward, a course Jindalee was urged to take after a violent death in 2006.

The inquest heard that the man suspected of the killing, who is now dead, had been in a fight and punched another man earlier that morning.

He was taken for breakfast, and then allowed to go back to his room.

Later that morning, a nursing assistant went into Mr McCulloch's room to hand out porridge.

He saw the shape of a body on the bed underneath a doona.

The worker pulled back the bedding to find Mr McCulloch with significant nose and face injuries. He appeared to be already dead.

Other staff were called, and came in to check. The registered nurse panicked, and went to her director of nursing Jo Costuna, telling her she was going to call the police.

But Detective Sergeant Sarah Casey told the inquest on Friday that the nurse was instructed not to call police, but instead to get a doctor in from the after-hours locum service.

"She was told not to because no one had seen what had happened," Detective Sergeant Casey said.

That's despite staff already suspecting that Mr McCulloch had died at the hands of another resident.

The decision created a significant delay between the discovery about 8am, and the eventual call to police at 8.53am.

It also appeared to have been out-of-step with one part of Jindalee's policy, which directs staff to call police first should they believe a coronial-related death has occurred.

In the meantime, the scene was left unsecured, Mr McCulloch's body was left unsupervised, and the man staff suspected to be the killer was left free to roam the ward.

Detective Sergeant Casey said there was evidence the body was interfered with, and a doctor later found a pillow had been placed over Mr McCulloch's face.

When they eventually arrived, police also found paper napkins shoved down his throat, something that may have contributed to his death.

The suspect, whose name is suppressed, was left in the same room as the body for periods of time.

He is also thought to have assaulted three others in Jindalee that morning, with the victim of the earliest attack later telling police:

"He grabbed my hair, he grabbed my throat. I'm afraid he's going to kill me."

Staff later found another resident with facial injuries, her head covered by a bloodied pillow. The woman survived the attack.

The inquest will also explore the appropriateness of staff-to-resident ratios at Jindalee.

It heard the registered nurse looking after the dementia ward was also taking care of another three wings, and 60 people in total.

Police say that an individual care plan had not yet been made for Mr McCulloch.

The inquest will explore whether interim care plans should be developed for new residents.

The hearing is expected to continue on Tuesday before Coroner Peter Dingwall.