NT cop Zachary Rolfe has told a court that the 19-year-old Aboriginal man he is charged with murdering, Kumanjayi Walker, tried to grab his gun during the fatal arrest.
Constable Rolfe made the previously unheard accusation from the witness stand during his second day of giving evidence in his own murder trial in front of a packed Darwin courtroom on Thursday.
During questioning from his barrister, David Edwardson QC, Constable Rolfe stepped the jury through his version of events on the night of November 9, 2019, when he shot Mr Walker three times in the chest, killing him, in the central Australian community of Yuendumu.
He said after approaching Mr Walker and initiating the arrest, Mr Walker began to attack him.
"He raised his arms, he started striking me around the head and neck area, he struck me twice on the top of my head in a hammerfist motion," Constable Rolfe said.
"I thought this was strange because he wasn't using his knuckles...that was the first time I ID'd that he had a metal blade protruding [from his hand].
"As soon as I saw the blade I feared for my life."
He said Mr Walker then made a move for his gun.
"I realised his left hand was already on my glock, I twisted my hips backwards to knock that hand off my glock."
He said he fired the first shot, which is not the subject of criminal charges, after Mr Walker stabbed him in the shoulder with the scissors while he, Mr Walker and his partner, Remote Sergeant Adam Eberl, were all standing up.
Then he fired the second and third shots, he said, because he believed Sergeant Eberl's life was still in danger, despite Mr Walker now being pinned to a mattress on the floor underneath Sergeant Eberl.
"I could see Kumanjayi's right arm was still moving and stabbing Eberl on the ground," Constable Rolfe said.
"I believed I hadn't incapacitated him at all [with the first shot]."
The court has previously heard from expert witnesses that Mr Walker's arm was likely at least partially pinned underneath his body.
Constable Rolfe then told court that he didn't "feel comfortable" that Mr Walker was no longer a threat until he had handcuffed him, put him in the back of a police car and removed his pants to search him for other weapons.
He explained the way he believed his actions had complied with his training, pausing to enthusiastically explain specific terms to the jury and gesturing with his hands.
The crowd in the body of the courtroom has swelled in recent days as more and more supporters of Mr Walker, all dressed in black, have filed in to witness the final days of the historic trial.
A number of police witnesses who have previously given evidence in the trial - star prosecution witness Detective Sergeant Andrew Barram among them - also appeared to watch Constable Rolfe from the witness stand.
In cross-examination, Constable Rolfe was asked by Crown prosecutor Philip Strickland if he utilised what's known as a "double tap" when he fired the second and third shots into Mr Walker's back in quick succession.
Constable Rolfe said he wasn't aware at the time that he was using that technique, and volunteered to explain to the jury the difference between a "double tap" and a "controlled pair."
"No, thank you," Mr Strickland said.
The court heard Constable Rolfe had applied before the shooting to be a part of the NT's specialist Territory Response Group as well as to return to the defence force to become a member of the SAS.
"To be honest, at that point in time I was in a bit of a rut in the police force and I was looking at other career paths," Constable Rolfe explained.
Mr Strickland asked if Constable Rolfe like the "excitement" and "adrenaline" of being deployed on arrests in high-risk situations.
"Not particularly," Constable Rolfe replied.
The cross-examination will continue on Friday.
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