A man with "many convictions" was helping a friend when he armed himself with a long carving knife before storming into a unit, grabbing a machete and inflicting injuries on a victim before his own blood trail led police to him.
The ACT Supreme Court on Thursday heard Villiam Bo Pikula, armed with a long carving knife, and another man, armed with a baseball bat or something similar, went to a Reid unit in July 2021 where they were examining a lock on the screen door.
The victim, who saw the duo, wearing COVID masks and dark clothes, via a baby monitor, grabbed a machete and confronted them.
He and a woman in the unit tried to stop Pikula, 39, and the alleged accomplice, who remains unknown to authorities, from entering.
Once they broke the screen door and entered, the victim used his machete to strike Pikula while two dogs inside the unit also attacked the offender's legs.
Pikula wrestled the machete from the victim and threatened to cut his head off before striking him on the forehead.
A fight ensued for a short time before the offender and his alleged accomplice left.
A woman in a neighbouring unit called the police.
When paramedics arrived, they saw an 8cm cut on the victim's head and injuries to a forearm and his hands.
Police followed a blood trail from the unit for about 400m to another residence where they found Pikula bleeding from lacerations.
They also found a blood-stained knife and metal bar near the offender.
The victim, in his impact statement, wrote he continues to have anxiety and daily flashbacks from the attack.
His friends have also avoided him because of his irrational mood swings and he has noticed a difference in his short-term memory.
The victim said one of his dogs, who was present during the attack, was less close to him.
The court heard Pikula, who pleaded guilty to aggravated burglary and assault occasioning bodily harm, said he was helping his friend, who had an issue with the victim.
On Thursday, the defence called on psychiatrist Dr Richard Furst to give evidence about his diagnoses of the offender having ADHD, substance use disorder and schizophrenia.
During cross-examination, Dr Furst said his ADHD diagnosis was based on the offender's difficulties only in a school environment and agreed the criteria for confirmation of the disorder needed at least two environments.
However, he maintained his diagnoses but admitted Pikula's diagnosed schizophrenia had little to no connection with the offending.
Defence lawyer Jonathan Cooper argued for a "lenient ratio" in relation to non-parole and parole periods.
"The reason is he's got a terrible record," Mr Cooper said.
"What does come through [in the record] is that he was working hard in custody. That's the reason for a longer period on parole and supervision for him to have that support in the community."
Mr Cooper also said his client suffering injuries reflected a degree of extra-curial punishment.
Crown prosecutor David Swan said the offending had a high objective gravity based on the number of aggravating features.
These included at the time of the offending, Pikula was on parole following convictions for similar offending - including break and enter and assault - in NSW.
Mr Swan said the court should "take issue" with the defence submission about non-parole because of numerous factors, including Pikula's criminal history speaking "to his low prospects of rehabilitation".
He said there was evidence showing him declining to participate in support services.
Justice Michael Elkaim said Pikula's injuries did not mitigate the seriousness of the offending.
"The fact that the injuries were caused during the fight must be seen against the background of the offender arriving with a large knife," he said.
"The presence of the knife indicates the malicious intent of the offender."
He said a sentence without a rehabilitation component was the wrong approach because being 39 was still an age "where there is a prospect of a decent future".
However, he said Pikula's danger to society and the need to deter others must also be considered.
The judge, who described Pikula's criminal history as having "many other convictions in NSW", sentenced the offender to four years and four months' jail, backdated to last July when he was arrested.
With a non-parole period of two years and six months, he will be eligible for release in January 2024.