A 19-year-old Aboriginal man was “in many respects the author of his own misfortune” when shot dead by a Northern Territory policeman, his murder trial has been told.

Constable Zachary Rolfe, 30, has pleaded not guilty to murdering Kumanjayi Walker as he resisted arrest in Yuendumu, 290km northwest of Alice Springs.

Defence lawyer David Edwardson QC told the Northern Territory Supreme Court on Wednesday the death of the 19-year-old on November 9, 2019 was a tragedy.

“A young man has lost his life and a young courageous police officer has been charged with the most serious charge known to criminal law,” he said during his closing address.

He said his client was arrested within four days of the shooting without a meaningful or proper investigation.

“That, you might think, is a disgrace,” he said.

“The executive of the NT police force and those they have deployed to justify these charges have thrown everything at Zach Rolfe because it was a decision that should never have been made.”

He said Mr Rolfe’s prosecution was the NT police force executive attempting to “justify what was the unjustifiable”.

“They had 841 plus days since the decision was made to charge Zach Rolfe and actually produce a case,” he said.

“The Crown produced 40 witnesses to support the narrative that Rolfe, a police officer, was guilty of murder.

“We say they have not come close.”

Mr Edwardson said almost all witnesses had confirmed that Mr Rolfe had acted as he was trained and his response when he fired three shots was reasonable and proportionate.

“Let us be brutally frank about this young man,” he said referring to Mr Walker.

“The truth of the matter is that he had a lengthy and violent criminal history.”

He said Mr Walker had threatened two other police officers with an axe on November 6 “in an extraordinarily dangerous and confronting manner”.

“Which of its self would have justified him being shot,” he said.

“Worse still, on November 9 he deployed a lethal weapon, namely the scissors, but this time he stabbed Zach Rolfe before turning his attention to (Sergeant Adam Eberl, then a constable).

“He might have been a young man and for that reason if nothing else, this case is tragic, but nonetheless he was dangerous and violent, and in many respects the author of his own misfortune.”

Earlier, prosecutor Philip Strickland SC said Rolfe had not seen Mr Walker stabbing Sgt Eberl in the neck and chest as he said he did.

He also said Rolfe’s testimony that Mr Walker reached for his police pistol was “made up” and a major problem for the constable.

“The evidence that Kumanjayi’s left hand is on the Glock (pistol) is a lie,” he said.

Mr Strickland said police body-worn camera footage does not support the claim and highlighted how Rolfe had not alerted Sgt Eberl to Mr Walker’s hand being on his gun.

“He goes back to the police station and never tells (Sergeant Julie) Frost that (Walker) went for his gun … does not tell any other officers,” Mr Strickland said.

“There is an obvious explanation why he does not say ‘gun’ at the time … and that is because that never happened.

“He made it up.”

Mr Strickland told the jury that if it accepted the lie about Mr Walker’s hand being on his gun it was “extremely damaging to the assessment of (Rolfe’s) credibility” that he also believed Sgt Eberl’s life was in danger and that he was being stabbed in the chest and neck.

“The Crown says he did not see (Walker) stabbing Eberl,” he said.

He also questioned Rolfe’s statement to his partner after he had shot the 19-year-old man: “It is all good. He was stabbing me, he was stabbing you”.

“It was a lie to justify the unjustifiable. He was saying it because he knew he had gone too far. He knew he had been too gung ho,” Mr Strickland said.

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