A jailed killer serving life for murdering an innocent teenager has been given an extra three months for beating a prison officer with a sweeping brush.
Brian Willoughby (42), who is 17 years into his sentence for killing Brian Mulvaney (19) in a frenzied attack in south Dublin in 2000, hit the guard when he was asked to walk to his cell.
Judge Bryan Smyth imposed the three-month term, but made it concurrent to his existing life sentence.
Willoughby, formerly of Orwell Park Drive, Templeogue, pleaded guilty to assaulting the officer in Mountjoy Prison.
Garda John Costigan told Dublin District Court the incident happened last July 7.
The accused was asked by prison staff to return to his cell and he refused to do so.
Willoughby picked up a sweeping brush and hit the officer across the back.
The court heard the victim suffered soft tissue damage but had since made a full recovery.
There was no medical report on the injury before the court.
Willoughby was "very sorry" for the assault and apologised, solicitor Murrough O'Rourke said.
He was serving a sentence for murder and had been in custody for 17 years.
Willoughby came from a "very nice family", but had some psychological problems and got into "more and more difficulty", Mr O'Rourke said.
It was a "very sad story".
"I think he was frustrated at the time," Mr O'Rourke said of the assault. "He very much regrets the incident."
Gda Costigan said the murder conviction was imposed in 2003 and the accused had a total of five previous convictions. The others were for assault.
Judge Smyth said the three-month sentence was to run from the date of conviction.
Willoughby sat in the dock wearing a face mask and was not required to address the court during the hearing.
He murdered student Brian Mulvaney in a frenzied attack in Temple- ogue, Dublin, on March 10, 2000.
During the attack on Mr Mulvaney, who was targeted because Willoughby was jealous of his friendship with a girl, the killer yelled: "Ha, ha, ha, this is carnage boys. This is deadly."
He told gardaí: "I was kicking him and jumping on his head when he was on the ground. I went berserk."
Willoughby was given a concurrent two-and-a-half-year sentence in 2018 when he admitted an assault on another prison officer.
In that case, the officer was on duty on December 31, 2017, supervising inmates during lunchtime when he felt punches to the back of his head.
Turning around, he saw it was Willoughby and radioed for assistance. Another prison officer arrived and Willoughby was restrained.