The agreed facts state that Mr Walker was an "arrest target" for NT Police after he breached a court order by cutting off his ankle monitor and fleeing a residential rehab in Alice Springs in late October, 2019 to return to his home community of Yuendumu, around three hours away, for a funeral. Police in Yuendumu attempted to arrest him on November 6 when Mr Walker ran at them with a small axe, causing them to back away and allowing Mr Walker to escape.

The accused, Zachary Rolfe, was a member of the Alice Springs Immediate Response Team (IRT) which was deployed to Yuendumu on November 9 for a number of reasons, including to assist with the arrest of Mr Walker. Less than an hour after Mr Rolfe arrived in Yuendumu, he had found Mr Walker and tried to arrest him when Mr Walker pulled out a pair of surgical scissors and stabbed him in the left shoulder, prompting Mr Rolfe to shoot him in the chest. Mr Rolfe's partner wrestled Mr Walker to the ground, at which point Mr Rolfe fired off two more shots at close range. It is these two shots that are the subject of the murder trial, with the prosecution deeming the first as justified.

Mr Walker died in the Yuendumu police station from his injuries around an hour later and Rolfe was arrested and charged with murder as well as two lesser alternative charges, all of which he has pleaded not guilty to.

So those are the basics, here is what we've learnt from the trial so far:

In his lengthy opening address for the Crown, which stretched over the first two days of the trial, Mr Strickland showed the court the footage of Mr Walker's last moments and the time leading up to it. He told the court the prosecution case would be that Rolfe "deliberately" fired the three shots at Walker, "the last two at point blank range", and intended to kill him or, at least, cause him serious harm.

"This rapid discharge of shots with a semi-automatic gun is sometimes called a "double tap" in police and military circles and the "double tap" is designed to ensure maximum injury or death," Mr Strickland told the court.

In that footage, Mr Walker is heard calling our for his mother as he lies bleeding on the mattress after the third shot is fired.

He is also heard to say "you mob been shoot me" and "I'm going to kill you mob."

Mr Rolfe's partner, Constable Adam Eberl, is heard to say "Did you - f***," which Mr Strickland said could be a reference to the shooting. Mr Rolfe replied: "It's all good, he was stabbing me, he was stabbing you."

Zachary Rolfe shows other officers his injury in the Yuendumu police station after the shooting of Kumanjayi Walker.

"Did he say those words because he knew that he had gone too far when he fired the second and third shots?" Mr Strickland asked the court.

"In other words, when he said those words, 'He was stabbing me, he was stabbing you', he knew that the shots were not necessary or reasonable.

"He knew that everything he'd done was captured on the body-worn video. In short, he said those words in order to justify what he had done."

In his comparatively brief opening address, Mr Rolfe's lawyer Mr Edwardson flagged that a phrase used religiously in NT Police training would form a major part of the defence case throughout the trial.

"Knife equals gun" or "edged weapon equals gun" means when police officers are confronted with a blade of any sort, they should draw their firearm and "be prepared to use it," Mr Edwardson told the court.

"That expression 'edged weapon equals gun' will loom large and ripple through almost all the police witnesses in this case."

Mr Edwardson said he will argue that Mr Rolfe was therefore simply following his training when he did what he did on the night of November 9, 2019.

"It will be the defence case through the various prosecution witnesses that are to be called that Constable Zachary Rolfe did no more than respond in the way in which he had been trained," Mr Edwardson said.

"That shot was in response to Mr Walker's deployment of the edged weapon against Constable Rolfe before, on the defense case, turning his attention to Constable Eberl."

"That expression 'edged weapon equals gun' will loom large and ripple through almost all the police witnesses in this case."

Mr Edwardson has kept to his word, asking most of the police witnesses called to give evidence thus far if they are familiar with the phrase and what it means to them. Not every officer had exactly the same interpretation, however, which leads to...

The court then heard extensive evidence about an incident which took place in Yuendumu three day's before Mr Walker's death.

Two local police officers, Senior Constable First Class Christopher Hand and Senior Constable Lanyon Smith went to Mr Walker's house in the evening to arrest him. However, Mr Walker pulled out a small axe from the corner of the room and came at the officers. The officers backed away without drawing their weapons, allowing Mr Walker to flee the house. They gave chase but didn't catch him.This incident and the one that followed, which saw Mr Walker shot three times by Mr Rolfe, were compared and analysed extensively.

Senior Constable Hand and Constable Smith were among the first witnesses to give evidence, and were asked about their approach to the incident.

Senior constable Hand said policing was done differently in Aboriginal communities to urban areas, and was heard on body worn footage after the incident warning Mr Walker's family that "he might be shot" if he did what he did to an Alice Springs cop.

Both officers said they aimed to have as little violent confrontation with community members, who they tend to know personally.

"I didn't feel that he was going to hurt me," Constable Smith replied.

"Kumanjayi, being a Warlpiri man, it was more of a show to his partner, who was in the room, and his family.

"But he just wanted to get away."

They both agreed that "edged weapon equals gun" had been a part of their training, but said there were other things to consider.

"It's a combination of training and knowledge of Kumanjayi," Constable Smith said.

"...by me drawing my Glock, there was a possibility that that may escalate him as opposed to de-escalating."

Next the court heard all about the events leading up to the shooting, which took place around 7.20pm on November 9, 2019.

The five members of the IRT arrived in groups, with Mr Rolfe arriving with another officer Constable James Kirstenfeldt. The court was shown CCTV footage of their arrival and their subsequent interactions with the team in the Yuendumu police station. The group arrived with a lot of gear, including two beanbag shotguns and two AR-15 rifles.

In her evidence, the Officer in Charge in Yuendumu at the time, Sergeant Julie Frost, told the court she found Constable Kirstenfeldt in particular to be "very dominating" in the time before they set out into the community.

"It appeared he was trying to take over the conversation and would not listen to me," she said.

There was also a lot of discussion around the operational plan Sgt Frost had devised for the IRT for their time in Yuendumu which included conducting "high-visibility patrols" and looking after any jobs overnight, as well as gathering intelligence about where Mr Walker might be. The plan was to arrest Mr Walker at 5.30 the next morning, but members should arrest him if they happened to come across him.

Out in the community, body worn footage shows that the weapons being carried by the IRT were attracting attention from locals.

One woman approached Mr Rolfe's partner, Constable Eberl, and asked why another member of the team was openly carrying a gun without a holster, saying "he's got it like aimed to shoot someone".

"He was probably referring to Hawkings [a team member] who was carrying an assault rilfle," Mr Strickland told the court.

Constable Eberl is heard to reply: "Someone probably shouldn't run at police with an axe, yeah?" which was presumably a reference to "the axe incident."

Body worn footage shows that Mr Rolfe and his partner straight away started asking community members about where he was and entered the house he was in at 7.20pm. The three shots had been fired by 7.23pm.

Despite Sgt Frost telling the court the IRT was not supposed to be arresting Mr Walker at that time, Mr Edwardson - in cross-examination - asked how they were going to carry out the arrest the next morning when they didn't know where Mr Walker was.