The ringleader of a group that bashed a convicted murderer in jail was motivated by what he had heard about the man's crime, a Hunter court has been told.
Richard Exton - one of three men charged with attacking Carly McBride's murderer Sayle Kenneth Newson in the maximum security wing of Cessnock Correctional Centre in June 2021 - was sentenced to a 15-month prison term when he faced Cessnock Local Court on Wednesday.
It came after he pleaded guilty in December to one count of assault occasioning actual bodily harm while in company.
But an "extremely strong subjective case" and a risk of Exton being institutionalised led Magistrate Ian Rodgers to set a one-month non-parole period, which meant he was eligible for release on Wednesday afternoon.
The balance of his sentence will expire in April 2025.
The attack took place four days after Newson was found guilty of murdering Ms McBride. The jury found that Newson struck the 31-year-old mother-of-two to the head several times before he dumped her body near a quiet stretch of road outside Scone in September 2014.
Magistrate Rodgers found beyond reasonable doubt that Exton was the member of the trio who smashed a plastic kettle on Newson's face inside the second-floor cell of the maximum security wing.
Exton's solicitor argued that his client did not strike Newson with the kettle and, given that all except what happened inside the cell was recorded on CCTV, it could not be concluded for sure what took place out of the camera's view.
The CCTV footage showed Exton and his two co-offenders - Christopher Dale Williams and Denham Hedges - enter Newson's cell and shut the door for a short time before all four, including an injured Newson, exited and a fight broke out on the walkway. Exton was carrying a broken kettle when he left the cell.
The footage showed Exton punch Newson, who suffered several facial fractures, several times.
Magistrate Rodgers said it was an "almost inescapable inference" that Exton hit Newson with the kettle.
He said it was not up to Exton to "extract punishment" for details he had heard about other offenders' crimes.
"It's clearly an extremely serious example of an assault charge within a custodial setting," he said.
"Violence in jail must be dealt with in a highly deterrent fashion."
But he said Exton's background and the risk of him being institutionalised mean special circumstances needed to be taken into account when sentencing him.
Hedges and Williams were previously sentenced to Intensive Correction Orders for nine and 15 months respectively.
