A QUEENSLAND teenager who compared thoughts of killing to the excitement of a theme park ride has been jailed for life for fatally stabbing another boy.
Jackson Bradey, 15, was walking alone near a Gympie shopping centre, about 160km north of Brisbane, after his last day of school in 2009 when the 16-year-old attacker stabbed him in the back with a bayonet.
When Jackson fled, his assailant, who is now 18 and cannot be named for legal reasons, chased after him as Jackson cried, "Help me, help me, I've been stabbed," the Supreme Court heard on Monday.
Witnesses said he followed Jackson into a car park, saying, "I am going to kill you".
The teenager had taken the bayonet after arguing with his mother about inappropriate photos of his young female cousins and his aunt on his phone, the court was told.
Sentencing him to life behind bars, Justice Ann Lyons told him his lack of empathy and remorse meant he was very dangerous person.
"I consider this to be a particularly heinous crime. It involved violence of a random nature against a person you did not know.
"I consider this offence was calculated, cold-blooded and for your own gratification.
"You have shown no remorse or empathy. There was no objective evidence of psychosis, you were just angry. I consider you to be very dangerous," she said.
As Jackson's family wept, Justice Lyons said she hoped the teenager realised the damage he had done to them.
"I hope you have observed the distress of the family of the boy you killed. Just think about that for one moment.
"This family have grieved and are grieving because of what you did, and you will have to think about that for the rest of your life," she added.
The attacker did not know his victim, a year 10 James Nash High School student described as a popular boy who loved singing and dancing.
The court was told that when witnesses tried to intervene in the slaying, the boy called out, "Do you want some, too?".
A man was stabbed in the back and suffered minor injuries trying to wrestle the teenager.
The teenager poked out his tongue, made faces and blew kisses as he was driven from the scene by police.
He later told police he heard voices telling him to stab someone and he chose Jackson because he was alone.
In various interviews and psychological assessments, the teenager said he enjoyed the adrenalin of the stabbing and the looks on faces of the witnesses.
One report said the boy had thoughts, dreams and daydreams of killing people.
"They excited him heaps, and he said it was like the adrenalin rush of a theme park ride," the report said.
"He said he always wanted to do it and he thought about killing someone with a gun, but it was not as good because it was too quick."
Another report said he had "violent, sadistic, murderous fantasies of stabbing men and watching them die and engendering horror in the witnesses".
Justice Lyons said she accepted he was not deprived of the requisite capacities as ruled by the mental health court, but said he had a psychiatric abnormality that was a mitigating factor.
The teenager, who pleaded guilty to one count of murder and one count of acts intended to maim, disfigure or disable, sat quietly in the dock as the sentence was passed.
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