The scissors used by Yuendumu man Kumanjayi Walker to stab police officer Zachary Rolfe in the shoulder before he was fatally shot could not have caused lethal injuries in the circumstances, a medical expert has told the constable's murder trial.
WARNING: Aboriginal and Torres Strait Islander readers are advised that this article contains an image of a person who has died, used with the permission of their family.
Mr Walker died about an hour after Constable Rolfe, 30, shot him three times during a struggle and attempted arrest inside a house in the remote community in November 2019.
Constable Rolfe has pleaded not guilty to murder, as well as alternative charges of manslaughter and engaging in a violent act causing death.
Government forensic pathologist Marianne Tiemensma told the Northern Territory Supreme Court on Tuesday that she did not believe Constable Rolfe or his partner were at risk of serious injury or death during the struggle with Mr Walker.
Dr Tiemensma, who performed Mr Walker's autopsy, told the court she was also asked by investigators whether the medical scissors used by the 19-year-old had the capacity to cause a "penetrating injury".
She said, in her opinion, the blades of the scissors were closed at the time Constable Rolfe was struck with them, meaning they had a thick blunt tip.
She said body-worn footage showed there was also a "very short window of opportunity for any meaningful attack" and that Mr Walker was "immediately restrained" by officers wearing clothing which would have caused "additional resistance".
"In these circumstances, I don't think that pair of scissors would have caused fatal injury to the carotid artery," she told the court.
Under cross-examination from defence barrister David Edwardson QC, Dr Tiemensma agreed she had very rarely seen stab wounds caused by scissors in other cases but said: "Fatal stab wounds by scissors are not common."
She rejected a suggestion by Mr Edwardson that she was seeking to "distance" herself from the notion that Mr Walker's scissors could inflict lethal injuries.
"If [the weapon] was a very sharp, thin tapered knife, I would have given an opinion based on that," she said.
"If you ask me for my opinion — that's what I believe."
Under cross-examination, Dr Tiemsensma confirmed she told investigators she was not the appropriate person to ask for an opinion on the injuries to Constable Rolfe and his policing partner.
The court heard she referred investigators to other experts instead, saying she wanted to avoid any perception of bias based on the fact she had conducted the autopsy.
The court has previously heard Constable Rolfe suffered a small puncture wound to his shoulder after being struck with the scissors before he fired the first of three shots.
Mr Edwardson has previously told the court Constable Rolfe was acting in defence of himself and his partner, as well as in line with his training and duties.
Constable Rolfe's partner begins evidence
On Tuesday, the court also heard from Sergeant Adam Eberl, who was with Constable Rolfe and involved in the struggle with Mr Walker when the shots were fired.
Sergeant Eberl confirmed that prior to travelling to Yuendumu from Alice Springs, he and other members of the police unit being deployed watched body-worn camera footage of Mr Walker threatening two Yuendumu-based officers with an axe several days earlier.
Asked by the prosecution to describe his impression of the footage at the time, he told the court: "I said: 'Wow, I'm surprised they didn't use the firearm'."
The court was also shown a section of Sergeant Eberl's body-worn camera footage from the night of the shooting, in which he is shown entering the front yard of the house where Mr Walker was then found.
A woman holding a crying baby asks why one of the officers is carrying a gun.
In the footage, Sergeant Adam Eberl replies: "No, he's not aiming to shoot anyone, is he?"
"We don't have a holster for that one, we have to carry it."
He adds: "So someone probably shouldn't run at police with an axe."
Soon after, the footage shows Sergeant Eberl and Constable Rolfe confronting Mr Walker inside the house.
Sergeant Eberl told the court he did not consider Mr Walker to be dangerous at that stage, nor did he consider withdrawing from the house and setting up a cordon.
He said he had no knowledge of a plan that the court has heard was developed by Yuendumu officer-in-charge, Sergeant Julie Frost, to arrest Mr Walker early the following morning.
The trial continues tomorrow, with Sergeant Eberl expected to continue giving evidence.
