A gangland "executioner" who waited four years to take revenge on a prison officer for seizing a phone from his cell has been jailed for a minimum of 45 years for his murder.
Armed robber Elias Morgan shot father-of-three Lenny Scott six times outside a gym in Skelmersdale, Lancashire, on 8 February 2024.
Investigators at HMP Altcourse in Liverpool discovered evidence Morgan was having a sexual relationship with a female officer called Sarah Williams after the phone was found in March 2020.
Police said Mr Scott had been "assassinated" by Morgan, who was described as a "cold-blooded executioner who took a mans life doing his job".
Det Ch Insp Lee Wilson said Mr Scott was a "man of huge integrity and bravery who did the right thing and who sadly paid the ultimate price by doing so".
Sentencing Morgan to a life term, judge Mr Justice Goose told him he was satisfied the murder was a "revenge killing" for what Mr Scott "did lawfully in his duty as a prison officer".
"The murder of the deceased has caused profound grief to the deceaseds family, his young children and all who knew him," he said.
"He was 33 with most of his life ahead of him.
"He was loved, he was respected and he made them proud."
Morgan listened to the sentencing at Preston Crown Court quietly after telling his barrister to say "nothing at all" on his behalf.
Caroline Goodwin, KC, representing him, told the court: "My very firm instructions are that I am to offer no mitigation, no submissions and no representations to the court."
The trial heard Morgan had offered Mr Scott £1,500 as a bribe to "lose" the phone when it was found.
When he refused, Morgan made a series of threats which "terrified" Mr Scott, including accurately describing his address, and what his partner and twin boys looked like.
At the time Mr Scott told his father, Neil Scott, that Morgan had said to him: "Ill bide my time, but I promise I will get you" before making a gun gesture with his fingers.
During the sentencing hearing Mr Scotts mother, Paula Scott, spoke to Morgan directly while giving statement.
She told him: "My son was everything you are not. He was strong, brave, honest, respectful, hardworking, kind, and principled. He stood for what was right.
"You are a violent, inhumane coward. I am hurt, I am angry, and I will never forgive you."
The court also heard from Lucy Griffiths, the ex-partner of Mr Scott and mother of his twin boys.
She described the pain of having to tell the boys, then six, of their fathers death and the struggles that followed.
Speaking from behind a screen, she said: "I find letters they write to him hidden under their pillow asking for him to come back, this is so upsetting to find as a mother.
"They have had nightmares about men chasing them with guns because of whats happened."
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