The defence lawyer for a Northern Territory policeman on trial for the alleged shooting murder of an Aboriginal teenager says his client was trained to draw his gun.

Constable Zachary Rolfe, 30, has pleaded not guilty to murdering Kumanjayi Charles Arnold Walker during a failed arrest attempt on November 9, 2019.

The 19-year-old died after he was shot three times in his mother’s home while he was holding a pair of scissors in the remote community of Yuendumu, 290km northwest of Alice Springs.

Defence barrister David Edwardson QC told the jury that Rolfe had been trained to draw his pistol and “incapacitate” when threatened by a person armed with a blade.

“He had been stabbed and his partner was locked in combat with an armed assailant with predisposition for violence,” he told the Supreme Court in Darwin on Tuesday.

“He was taught, trained and drilled as a member of the NT police force that edged weapon equals gun.

“In other words, when an officer is confronted with an edged weapon, the appropriate response is to draw your weapon and be prepared to use it.”

Rolfe did. 

He fired three shots into Mr Walker. The first shot is not the subject of the murder charge. It relates to the second and third shots, which the prosecution says were not legally justified.

“It is the defence position, that having been stabbed by a known violent offender and having lawfully shot him once, he was justified in continuing to defend his mate and fellow police officer.”

Mr Edwardson also cautioned the jury “to keep an open mind throughout the trial”.

“In this case more than most … intellect has to rule the heart,” he said.

Earlier, prosecutor Philip Strickland SC said Rolfe ignored a senior officer’s instructions for arresting Mr Walker.

He said Rolfe and his fellow officers had been told less than an hour before the shooting to “gather intelligence” in preparation to arrest Mr Walker the next morning.

“The accused and other (officers) chose to ignore that operational plan,” he said.

“When they left Yuendumu Station at 7.06pm, they were intent on finding and arresting him that evening.”

After Rolfe shot Mr Walker called out for his mother and moaned as the officers handcuffed him. He also threatened to kill them.

In the dark room as Mr Walker bled on to a grubby mattress on the floor, Rolfe told his partner: “He was stabbing me. He was stabbing you”.

Mr Strickland suggested to the jury that Rolfe may have said those words “because he knew he had gone too far”.

“He knew the shots were not necessary or reasonable. He knew everything he had done was captured on the body worn video,” he said.

“In short he said those words to justify what he’d done.”

Mr Walker died at 8.36pm after the officers had moved him to the local police station and “done the best they could to save his life”.

Either the second or third shots “fatally damaged” his spleen, kidney and right lung.

“He intended to kill Kumanjayi Walker, or cause him serious harm,” Mr Strickland said of Rolfe.

The trial continues on Wednesday.

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