AN INMATE who poured boiling water over Daniel Morcombe's murderer claimed he acted "as a voice for Daniel” because the slain teen could not speak out himself.
But a judge sentencing Adam Paul Davidson for the attack quoted Gandhi, saying "an eye for an eye” made the whole world blind.
Judge Ian Dearden admonished Davidson, 31, for attacking child killer Brett Peter Cowan but acknowledged hardships Davidson himself had endured.
He sentenced Davidson to three years jail, but with a parole release date of November 29.
Judge Dearden said even Cowan should be able to serve his sentence "being treated with respect” by other inmates and by prison authorities.
The judge said nobopdy was or ever should be entitled to "become a vigilante delivering retribution to someone else who happened to have been high profile”.
Defence barrister Stephen Kissick said his client claimed to have acted "as a voice for Daniel”, who could not speak out, but that should be understood in the context of Davidson's history and mental troubles.
Brisbane District Court heard Morcombe's killer screamed in pain and asked "why why why” when Davidson the water from a mop bucket on him and beat him at Wacol jail.
Mr Kissick said Davidson faced multiple mental health problems.
Davidson had symptoms consistent with post-traumatic stress disorder and in jail was only allowed out one hour a day, Mr Kissick said.
He suffered mental disturbances including previously being "in communication with a donkey”.
He was previously jailed in Rockhampton and Maryborough.
Mr Kissick said Davidson's risk to the community was not high, and he recognised the importance of addressing his mental health issues.
He was not the sort of person the community would regard as a torturer, the defence counsel added.
Prosecutor Mark Whitbread said Adam Paul Davidson was seen standing next to a laundry door "filling up a yellow mop bucket from the urn”.
Davidson asked another inmate to move, then approached Cowan.
"He had it coming ...That f***ing grub deserved it,” Davidson allegedly said after the incident.
The contents of the bucket left Cowan with "scalding” over 15% of his body, the prosecutor said.
Mr Whitbread said the offending last year "fell short of grievous bodily harm” so the charge was amended to torture, with an alternative charge of assault occasioning bodily harm.
Davidson pleaded guilty to torture on Monday morning.
The attack happened on August 5 last year.
Davidson previously lived in Toowoomba.
Cowan, now 48, was found guilty in 2014 of murdering Daniel. He was sentenced to life in prison.
13 year-old Daniel was abducted and murdered in December 2003 while waiting to catch a bus on the Sunshine Coast.
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