There is no dispute 34-year-old Senior Constable Kristian White discharged his stun gun at great-grandmother Clare Nowland at the Yallambee Lodge aged-care home in the southern NSW town of Cooma, 114km south of Canberra, in the early hours of May 17, 2023, and this led to the 95-year-old's death. However, the officer stands by his actions.

Defence barrister Troy Edwards SC told the NSW Supreme Court his client had a duty to protect others from injury or death and acted against the risk that Nowland posed by holding a knife and approaching him.

Crown prosecutor Brett Hatfield SC told jurors the use of force amounted to criminal negligence and a reasonable person could foresee the likelihood of serious injury.

The jury was shown the incident in footage from the aged care home's CCTV cameras, as well as body-worn cameras from White and his partner.

"We're not playing this game, Clare, you're going to put that down," White was heard saying as the resident approached them with a knife from inside one of the centre's treatment rooms.

Jurors heard electrical crackling come from the Taser as the policeman activated it but initially did not fire.

"You keep coming, you're going to get Tased," he told her.

As Clare kept walking forward despite the warnings, White was heard saying "nah, bugger it" before discharging his weapon.

The 95-year-old was seen taking the impact and hunching forward before falling backwards onto the floor, where she lay still.

"Got her, grab it, grab it, grab it," White yelled.

The trial is expected to last three weeks.

Yallambee Lodge has been acquired by aged care turnaround specialists Respect Aged Care, effective 1 April 2024, becoming their 25th aged care home.