A blood stain pattern expert has concluded that a man fatally shot by his step-father was near the ground when struck by one of the four bullets fired at him.

Bradley Thomas Danual Auckram, 52, has pleaded not guilty to murder, with his defence lawyer Linda Black arguing that he had fired to protect himself and his family after his stepson Jason Jeffrey Burton, 41, allegedly threatened to "slaughter" them if he was thrown out of the Clarkson home.

The State alleges Mr Auckram had reached the "final straw" after an argument at home with his stepson on June 8 last year following decades of a strained relationship between the pair.

Today, a blood stain pattern expert with the WA Police said spatter on the home's hallway indicated that one shot had struck Mr Burton's body at about 1.2m from the ground while another struck his head while it was almost at ground level and in a position similar to that in which his body was found.

The expert said testing found no blood on the rifle's barrel.

Prosecutor Dave Dempster alleges that Mr Auckram had purposefully killed his step-son and was enraged when he fired four bullets at him with a rifle in the family home's hallway.

One shot struck his arm, two struck him in the back and one struck his head, the prosecutor has said, with allegedly no words spoken before Mr Auckram opened fire from the end of the hallway.

Mr Dempster alleges there is no excuse for the fatal shooting and that Mr Burton had been defenceless and standing in the hallway with a cup of coffee when killed, while Ms black argues that her client had acted of fear for his and his family's safety.

The court has heard Mr Burton was a "troubled" man who was on a range of prescription medicine including anti-depressants and anti-psychotic medication, and allegedly reported nightmares of killing his stepfather to a psychiatrist.

The trial continues.

The West Australian

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