A veteran Northern Territory police officer has been accused of concealing evidence from the defence team for a constable accused of murdering Aboriginal teenager Kumanjayi Walker.
Sergeant Julie Frost was the officer-in-charge at Yuendumu police station, 290km northwest of Alice Springs, when Zachary Rolfe allegedly murdered the 19-year-old in a failed arrest attempt on November 9, 2019.
Lawyer David Edwardson QC on Friday accused Sgt Frost of lying under oath during Rolfe's committal hearing in September 2020 when she told an Alice Springs court there were no other notes about the fatal shooting other than those she had already disclosed.
But she agreed during a terse and protracted exchange that she had actually written a detailed chronology of the night Rolfe fired three shots into Mr Walker after the teen stabbed him with a pair of scissors.
"You knew perfectly well that those notes were disclosable and you deliberately chose to conceal them," he told the Supreme Court in Darwin at Rolfe's murder trial.
"Incorrect. It was rough notes," Sgt Frost replied.
"They were my aide-memoire. Notes I used to make my statement (to police investigating the shooting). I did not consider them to be necessary."
Mr Edwardson read Sgt Frost's testimony from the committal when she told the court she had brought all the notes about the incident to the hearing.
The chronology was not among them and only came to light when Sgt Frost provided it to investigators in November 2020.
He also pointed to differences between Sgt Frost's chronology, which were her first notes after the shooting, and her evidence to the murder trial.
The sergeant, who has been on the force for 17 years, has told the trial she briefed Rolfe and three other members of his Alice Springs-based Immediate Response Team to carry out a highly visible patrol around the remote community of about 800 and assist with general policing while the stretched Yuendumu policing team was resting.
The officers were also ordered to gather intelligence about Mr Walker's location in preparation to arrest him early on November 10.
Mr Edwardson said some of those orders were not mentioned in Sgt Frost's chronology and they were actually tasked with finding out where Mr Walker was.
The court has heard Rolfe and his team left the police station at 7.06pm and quickly located Mr Walker at a house about 15 minutes later.
Rolfe fired his first shot about 7.21pm as he and Constable Adam Erbyl attempted to handcuff Mr Walker, who was resisting arrest.
It was quickly followed by two more shots while Const Erbyl wrestled with the teen on the floor.
He died at 8.36pm from injuries sustained by one of those two shots, which the Crown says were not legally justified because Mr Walker was "effectively restrained".
The trial continues.