Warning: This story contains the name and images of a deceased Indigenous person.

A man accused of murdering an Indigenous teenager allegedly stomped on the boy and witnessed his co-accused attack him with a metal pole, a court has been told.

Aleesha Louise Gilmore, 23, her then-boyfriend Jack Steven James Brearley, 24, and his mates, Brodie Lee Palmer, 29, and Mitchell Colin Forth, 26, are on trial in the West Australian Supreme Court for Cassius’ murder.

Prosecutors previously said Brearley delivered the fatal blows while he was “hunting for kids” because somebody had smashed his car windows and alleged Forth, Palmer and Gilmore helped him and knew his intent before the incident.

But on Thursday, prosecutor Tracy Tan challenged Palmer’s evidence he wasn’t at the scene when Cassius was struck and that he offered to help the teen after he was injured.

“You were holding a pole at the time you ran into the bush?” Tan said.

Palmer replied: “No, that’s incorrect.”

Tan: “You saw Jack with a pole too, hitting Cassius?”

“And you then kicked Cassius yourself at least once … or stomped on him … or you were otherwise close enough to strike him while Jack was striking him?” Tan said. 

Palmer said that was “incorrect”.

Brearley has denied hitting Cassius with a pole, claiming he only punched him after the teen knifed him and Palmer struck the fatal blows, which he also denies.

Palmer previously told the jury he was “full of piss” and waited in his ute near the bushland after Brearley ran into it with a pole in a “show of force” to deter a group of young people coming to Gilmore’s home.

He said he later heard Brearley yelling for help, saying he had been stabbed and he walked into the bush where he found Brearley standing over Cassius yelling, but he saw no pole.

“When I seen the kid he was lying on the floor covered in blood,” he said on Thursday, as Tan tested his evidence.

“I asked (Cassius) if he was alright. I asked him if he knew what day it was and I asked him if he was able to walk back to friends.”

Palmer agreed with Tan he had seen Brearley swing a metal pole at other teens, who were with Cassius before he was allegedly attacked, but said he was not aware Brearley “would go as far as he did”.

Tan also probed Palmer about his methylamphetamine use, which he has admitted.

Palmer agreed the drug made some people more aggressive and violent but denied he was using it on the day Cassius was injured.

The trial has heard that after Cassius was allegedly assaulted, the four accused drove to Gilmore’s nearby home, where Brearley attended to his knife wounds and Forth allegedly armed himself with a baseball bat and a pole, and said: “Let’s go back there and f*** everyone one of them up.”

Palmer agreed he would have driven the group “somewhere with weapons to hurt kids”.

“We were angry,” he said.

But he said he wasn’t sure what would have happened if he had, recalling that a fight broke out between Brearley and Gilmore and she self-harmed and they instead drove her to hospital.

For 24/7 crisis support run by Aboriginal and Torres Strait Islander people, contact 13YARN (13 92 76).