A QUEENSLAND prisoner who poured hot water over Daniel Morcombe’s killer in an act of “retribution” has been sentenced to three years behind bars for the vigilante crime.

But Adam Paul Davidson will be on parole in a month after Judge Ian Dearden decided to take “a chance” on the 31-year-old father of four. Davidson pleaded guilty in the Brisbane District Court on Monday to torturing Brett Peter Cowan at the high-security Wolston Correctional Centre in Wacol on August 5, 2016.

Davidson admitted to acting alone and told investigators the attack was “a little bit of retribution”.

“He had it coming, he’s a f***ing grub,” Davidson said.

The court heard Davidson, who was in custody for robbery and fraud offences at the time, watched Cowan’s movements for a month and plotted the best way to harm the notorious sex offender.

Prosecutor Mark Whitbread said Davidson got the idea to use hot water after he saw another inmate with horrific scars and wearing a burn suit from a similar attack.

“He just wanted to hurt him, just wanted him to feel the pain that somebody like Daniel Morcombe has felt,” Mr Whitbread said.

The court heard Davidson filled up a mop bucket from a hot water urn then tipped it over Cowan’s head while he was playing cards with other inmates. As Cowan screamed “why, why, why” in extreme pain, Davidson struck him in the head with the bucket three to four times.

Cowan was treated in hospital for superficial burns to 15 per cent of his body and has since recovered from his injuries.

Judge Dearden said Davidson had no entitlement to act as a vigilante and every person should be treated equally — even someone who had been convicted of an “appalling” crime.

“We are all precious human beings, it doesn’t matter who we are,” Judge Dearden said.

“His punishment is to be imprisoned, not to be the subject of physical, mental or other abuse.” Cowan, 48, is serving a life sentence for abducting and murdering Daniel on the Sunshine Coast in December 2003.

The 13-year-old’s remains were found in August 2011 after an elaborate police operation prompted Cowan to confess and lead undercover officers to where he dumped Daniel’s body.