By Emma Lawson
A double killer has had extra jail time added to his life sentence for attacking a prison guard.
Norman Carlton punched James Roy and struck him with a weapon consisting of a screw attached to a makeshift handle on February 17 last year.
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The 36 year-old was locked up in HMP Low Moss, Bishopbriggs in East Dunbartonshire, at the time.
He was sentenced to a minimum 22 years in 2013 for the murder of gangland figure Stewart Gillespie in Paisley.
Carlton, originally from Paisley, was previously locked up for the culpable homicide of a man when he was just 17.
He has now had an extra 22 months slapped onto his life sentence after he admitted assaulting Mr Roy to his injury.
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Prosecutor Carrie Stevens told Glasgow Sheriff Court: "A commotion was heard and a guard saw Carlton punch Mr Roy on the head."
Fellow inmate Mark Wright, 29, then suddenly joined in.
Miss Stevens: “Wright then struck Roy on the head and once he was on the ground kicked him repeatedly.
“Mr Roy pressed the staff help button and more officers came.
"Carlton was on top of Mr Roy at that time.”
“They attempted to restrain him by taking hold of his right arm and in doing so found that he had a weapon, which was a screw with a make shift handle.”
Carlton's lawyer Waqqas Ashraf said the killer apologised and that "matters got out of hand".
Wright was sentenced to ten months after he also pled guilty to assaulting the guard.
Sheriff Joan Kerr told the pair: “It was a significant act of violence that you both took part in.”
