Joshua Kettle , 30, was sentenced to three years and six months in prison at Preston Crown Court after attacking Richard Hamill, 39, at HMP Lancaster Farms last year.
Police had been called around 6.15pm on June 23, 2019, to reports a prisoner had been assaulted by another inmate, suffering a serious head injury. The victim, Mr Hamill, from Morecambe, was taken to Royal Preston Hospital for treatment but sadly died on June 28.
Following CCTV enquiries detectives found Kettle had approached Mr Hamill, leaning against a pool table in a recreation room, before striking him once in the chest.
Mr Hamill sadly collapsed and never regained consciousness.
Kettle was initially arrested on suspicion of assault in connection with the incident and released under investigation pending further enquiries.
A Home Office post-mortem found Mr Hamill had died after being struck to the chest, suffering a ‘blood hammer effect’, where a pressure surge travelled upstream within the blood vessels to the base of the brain.
Mr Hamill had a pre-existing natural disease, known as a Berry aneurysm, with two aneurysms identified during the post-mortem.
One of the aneurysms, next to the cerebral artery, had ruptured, with blood leaking into the brain causing a subarachnoid haemorrhage. This caused Mr Hamill to collapse, fall unconscious and sadly later die.
The post-mortem gave the subarachnoid haemorrhage and ruptured Berry aneurysm as the causes of death.
Following consultation with the Crown Prosecution Service, Kettle was further arrested and charged with manslaughter in March.
He pleaded guilty and has been sentenced to three years and six months in prison.