A policeman says he did not need to draw his own gun when Constable Zachary Rolfe fatally shot Kumanjayi Walker.

Rolfe has pleaded not guilty to murdering the 19-year-old during a failed arrest attempt in Yuendumu, 290km northwest of Alice Springs, on November 9, 2019.

He says he was doing his job when he shot Mr Walker three times and defending himself and Remote Sergeant Adam Eberl from a violent offender who had stabbed him in the shoulder with a pair of scissors.

Body-worn camera footage of the incident played in the Northern Territory Supreme Court on Wednesday shows Sgt Eberl, then a constable, hit and then forcefully grab Mr Walker seconds before Rolfe fires his first shot.

Sgt Eberl told the court he spotted a “sharp and pointy object” in the teen’s right-hand.

Asked why he did not also drawn his Glock pistol as Rolfe had, Sgt Eberl said he was not aware Mr Walker had a weapon when he started restraining him.

“When you did become aware why did you not draw it?” prosecutor Philip Strickland SC said.

“Because his right arm was out and it was not in front of me trying to stab me at that time,” Sgt Eberl replied.

“I took hold of his arm, and I used a distraction strike to try and change his mindset, and get him into a position to restrain him”.

Sgt Eberl is then seen holding Mr Walker from behind with his right arm around his neck and his left arm locked around the teen’s left arm before the pair fall to the ground.

This was described to the court as a “modified seatbelt hold”.

Prosecutors have conceded the first shot, which was fired while Mr Walker was standing and resisting arrest, was justified.

But they say the second and third shots went “too far” because the teen was “effectively restrained” on the ground by Sgt Eberl when Rolfe pulled the trigger.

Sgt Eberl described the sound of the first shot as a “dull thud” and said he thought it was another officer, Constable James Kirstenfeldt, firing a beanbag round from a shotgun.

“It is hard to determine at that stage what I was thinking other than to take the offender down,” he said, when asked to reflect on the incident.

Seconds later, Sgt Eberl has Mr Walker on the ground on his side and Rolfe fires the second and third shots into him from behind his colleague.

“I was trying to restrain him in the ground and I was holding his left arm with my arms … so he could not turn on me to try and get me with the weapon in his hand,” he said.

Asked where Mr Walker’s right arm and hand holding the scissors were at that time, Sgt Eberl said “I believe it is underneath his body”.

Sgt Eberl previously told the court he did not think Mr Walker was a threat to him or Rolfe as the teen walked towards them.

The officers had earlier watched body-worn camera footage of Mr Walker violently threatening two other officers in Yuendumu with an axe three days earlier.

The incident had contributed to the decision to send Sgt Eberl and Rolfe to the community.

The officers’ body-worn camera footage also shows Mr Walker telling the Rolfe and Sgt Eberl his name is Bernard Dixon and one of them ordering him to put his hands behind his back.

The teen does not comply and seconds later the men scuffle as he resists arrest. Mr Walker then stabs Rolfe in the shoulder with scissors held in his right hand before the three shots are fired.

The second fatal shot left a “gaping hole” in the teen’s right lung after ripping through his spleen, liver and left kidney.

The trial continues.

Canberra Daily would love to hear from you about a story idea in the Canberra and surrounding region. Click here to submit a news tip.