UPDATE: Three of the boys responsible for Tauri Litchfield's death have been sentenced to four-and-a-half years in juvenile detention.
The fourth boy, described by the judge as the "instigator", has received a sentence of five-and-a-half years for the manslaughter of Mr Litchfield.
The boys had their punishments backdated to last year and may be released on supervision after serving half the term.
One of the teenagers responsible for Mr Litchfield’s death was also a part of a group sex attack on a woman near a shopping centre in 2011, a judge has been told.
The 15-year-old’s criminal history was read out in the Perth Children’s Court as he and three other juveniles awaited punishment for manslaughter after the 28-year-old sailmaker fell and fatally struck his head as he ran from the group of boys in March 2013.
He had been walking home when he was pickpocketed and assaulted by one of the juveniles and was then chased by the group.
Today, lawyers for the boys argued that their clients had grown up without role models or without a stable family life, which in some cases involved removal by Department of Child Protection and abandonment by their parents.
The lawyers also suggested their clients were remorseful for the death of Mr Litchfield.
All defence lawyers highlighted the young ages of their clients, stressing they lacked the maturity and judgment of adults and that rehabilitation was a crucial factor to take into account when deciding their punishment.
They also stressed that the teenagers had spent more than a year behind bars awaiting the outcome in the case.
But prosecutor Amanda Forrester also pointed to two of the boys’ criminal records, suggesting it was relevant to their prospects of rehabilitation.
The court was told one of the boys, now aged 15, had been involved in another group attack in 2011 which had seen a 43-year-old woman targeted as she walked near a shopping centre at 3.10pm.
The woman had been subjected to aggravated attempted sexual penetration as the group surrounded her and attacked her.
The youth had also been involved in two other assaults.
A lawyer for another of the convicted boys unsuccessfully tried to prevent his client’s record being read to the court.
The prosecution revealed that the teenager had been convicted of an assault in 2010 in which he punched his victim and threw a brick at his face.
The victim had been selected at random after the teenager and his friends decided to assault someone.
Ms Forrest said one of the tragedies of the case was that Mr Litchfield had only by chance come across the boys on St Patrick’s Day last year as he walked home.
She said it was a chance encounter that saw him lying unconscious on the ground just 10 minutes later.
"None of the offenders rendered assistance to Mr Litchfield or sought it," she said.
"Mr Litchfield lay in that carpark for almost an hour before he was found."
Ms Forrest said while avoiding the delay may not have saved his life, it was a cruel thought for his family that he lay in that injured condition by himself.
The court was told one of the boys had suggested calling an ambulance before leaving with his offenders. He now regretted his inaction.
Earlier today Mr Litchfield's mother confronted the boys responsible for her son's death, reading a victim impact statement describing her grief and calling on them to change their lives for the better.
Kerryn Biggs this morning told the boys responsible for his death they would only understand her grief when they had their own children.
"Now instead of sharing his joy for life.... as a mother I am broken in a way that only a mother who has lost a child knows," she said in court.
"I will take this pain to my grave."
"We lost his memories, we lost his future.... our family had no choice."
"You have an opportunity to choose how to use the rest of your lives, to make a better future for your family, your community and your children," Ms Biggs said directly to the convicted teenager in the dock.
"There are no words that I can describe the agony and the anguish but when you have your own children them you will understand what you took from us."