But Paul Erskine, who attacked Samuel McIntyre with a razor blade in HMP Kilmarnock last Semptember, was already serving a 22-year sentence for murder and culpable homicide in September 2014.
He and fellow thug Andrew Moran brutally killed 65-year-old Harry Reekie and 31-year-old Steven Mitchell within just 36 hours.
Both teenagers at the time, the pair left the pensioner drenched in blood and tied up following the “unimaginable ordeal” at his home in Bathgate.
The horrific attack saw Moran try to cut off Mr Reekie’s ear after demanding he hand over thousands of pounds in cash.
The duo, both 19, then used £400 in cash stolen from the helpless 65-year-old to go shopping and drinking in Bathgate town centre.
In the early hours of the next day, the killers struck again – this time attacking Steven Mitchell, who Moran had bullied on previously occasions. The 31-year-old was stabbed to death at a house just yards from Mr Reekie’s home.
The callous teenagers then went for a McDonald’s meal together and boasted to friends about their “evil” actions.
But they were later caught when police found bloody footprints from their new trainers at the scene of the second attack.
The High Court in Glasgow heard in 2015 that the two victims had been subjected to “needless and grotesque” violence in the space of just 36 hours.
Moran was convicted of both murders following a three-week trial, while Erskine was found guilty of murdering Mr Mitchell and the culpable homicide of Mr Reekie.
Speaking after the case, Detective Superintendent Kenny Graham, who led the “extensive” investigation into the horrific incidents, described Erskine and Moran as “vicious killers”.
Det Superintendent Graham also described the actions as “wicked.”
The jury at the time heard how Moran and Erskine targeted Mr Reekie’s home in Lothian Street, Bathgate, at about 3am on September 16th, 2014.
The OAP had moved back to West Lothian from London to help care for his terminally ill brother, Colin, who had died shortly before the shocking attack.
Mr Reekie – who had battled cancer – woke up to discover the hooded duo in the living room of his home, where he lived alone.
They had climbed in through his window after breaking into a nearby house.
Moran ordered Mr Reekie to “sit there and shut up” before demanding £20,000.
When the terrified pensioner said he didn’t know what he was talking about, Moran tried to cut off his ear while Erskine searched for cash.
In her closing speech to the jury, prosecutor Angela Gray said: “[They were] torturing him in his own home where he should have been safe.”
Moran bound tape around Mr Reekie’s mouth and wrist, while he sat bleeding in a chair.
Mr Reekie offered the keys to his car in the hope that the men would stop his ordeal – only to be stabbed again by Moran.
Even as Mr Reekie tried to get help, Moran slashed him across the legs. The thugs eventually fled with £400 and several mobile phones.
Neighbour George Campbell found Mr Reekie “saturated in blood” with black and yellow tape wrapped tight around his neck.
Mr Campbell had rushed to the scene after hearing the pensioner’s cries for help.
The pensioner had a series of stab wounds on his chest, stomach, leg and arm.
Mr Reekie was later able to identify his attackers when questioned by police in hospital, saying he remembered Moran’s “fat face” and “stinking breath”.
The victim also recalled Moran “getting his jollies” by knifing him.
Mr Reekie told police the attack had left him terrified to return home and he remained “living in fear”.
He initially showed signs of improvement, but he sadly died in hospital on January 4 this year.
The jury heard that in the hours after the attack, the killers used the £400 cash to buy expensive clothes at the Nautica menswear store in Bathgate.
Moran treated himself to a Lyle and Scott jumper and New Balance trainers while Erskine bought a pair of Cruyff training shoes. They were captured on the shop’s CCTV. They also used the stolen cash to go drinking in the town.
Just a day later, the pair struck again – attacking Mr Mitchell at his home in Marmion Road, Bathgate.
The trial heard how Mr Mitchell – who is believed to have given the men access to his house – had previously told another man how Moran was “always trying to hit him” and was “bullying him”.
Mr Mitchell – described as a “loveable wee guy” – was stabbed a dozen times, including once to the heart, and struck with a hammer.
Moran and Erskine, who knew Mr Mitchell, have never revealed a clear motive for their actions.
Moran and Erskine were seen walking from the area at around 2am – leaving behind damning footprints from the new trainers they bought with Mr Reekie’s cash.
At the end of what prosecutors described as a “ghoulish 36 hours”, the pair went for a McDonald’s meal – as Mr Mitchell’s sister, Charlene, discovered her brother’s body.
Moran was alleged to have boasted to another man: “Paul stabbed him and I finished him off. I’ll do it again . . . have done it before.”
Erskine had previously admitted in court to being involved in Mr Mitchell’s murder, while Moran denied the killings. It was claimed he was a “fantasist” and a “wannabe gangster” who “talked nonsense”.
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