A Perth man who chased a teenage dirt bike rider, causing his death in a crash, was disqualified from driving at the time and also lied to police about his passengers, a court has heard.
Jude Nathan Francis, 26, was 25km/h over the speed limit when he tailed Mitchell Chase in Aubin Grove in December 2016, suspecting the 15-year-old was riding a motorcycle that had been stolen from him.
The pursuit caused the boy to look over his shoulder in fear at the offender's Mercedes, go through a give way sign and slam into another car.
Mitchell was thrown from the dirt bike and died in hospital the next day.
Immediately after the crash, Francis drove up to the intersection, observed the bike wasn't his and went home.
He didn't report the incident to police, although he told his parents the next day.
When officers came knocking, he confessed and was charged with three offences including manslaughter.
But he wrongly told them his two passengers were hitchhikers, the Supreme Court of WA heard during sentencing submissions on Tuesday.
Justice Bruno Fiannaca said claiming they were strangers - making them complicit in concealing the offence - could be viewed as an aggravating factor.
The prosecutor said that must be the case.
Francis had even suggested to police they broadcast details the investigation to prompt the "hitchhikers" to come forward.
"There was a degree of deception," the prosecutor said, describing the offending as "misguided vigilantism".
Parallels were drawn between the case and the death of Kalgoorlie teenager Elijah Doughty, who in August 2016 was run down and killed by a man who was trying to reclaim his stolen dirt bike.
Francis' defence counsel said his client had been "very much aggrieved by" the theft of his dirt bike and was also trying to retrieve it.
The lawyer said his client was test driving the car after it had mechanical problems, and went into shock after the collision.
"There was no talking in the car - everyone went silent," he said.
Francis was remorseful and wanted to apologise to Mitchell's family, but had not yet done so, the lawyer said.
In her victim impact statement, the boy's mother wrote about his final moments being filled with fear.
The court heard Francis was disqualified from driving at the time of the crash, having previously driven while his licence was suspended.
Justice Fiannaca said Francis would be sentenced to a term of immediate imprisonment on Wednesday.
He was remanded in custody after previously being released on bail.