NEVILLE Cifuentes poured petrol over a workmate and set him on fire and no one knows why.
His 21-year-old victim suffered horrific, painful and life-threatening burns and is permanently scarred for life.
The best excuse Cifuentes could come up with was "mucking about or horseplay".
The incident happened at Kuttabul, about 35km north of Mackay, on July 15, 2008, when Cifuentes and his victim were Queensland Rail contractors working on a train line.
However, it wasn't reported to police until January last year, some two years and three months after it happened.
Cifuentes and his victim were standing near a parked truck waiting for work to be done when Cifuentes picked up a can of petrol, Crown prosecutor Chris Winlaw told the District Court in Mackay on Friday.
Cifuentes said to his workmate: "Do you want to see something burn?"
He looked around and said: "There's nothing here. You'll do."
He splashed petrol over his workmate's left arm, shoulder and chest, then got out a cigarette lighter, smiled, and started flicking it.
The victim said: "F... off" and turned to move away.
That was when Cifuentes set him on fire.
The victim fell to the ground, rolling around trying to put out the flames, and other workmates ran over to help him.
He immediately suffered severe burns to the left side of his body, skin was hanging off him and he was bleeding.
Co-workers gave first aid and drove him towards Mackay, meeting up with an ambulance on the highway.
The victim required extensive skin grafts to 6% of his body and suffered soft tissue infections which required antibiotics.
Mr Winlaw described the act as one of monumental stupidity: "They apparently were friends and it seems like horseplaying gone wrong."
Cifuentes, 26, pleaded guilty to causing grievous bodily harm.
Defence barrister Paddy Cullinane agreed it was an offence of gross stupidity "mucking about or horseplay".
Cifuentes was jailed for three years, to be released on parole on September 23 next year.
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