A pensioner who attacked and killed a sleeping man with a spade has been sentenced to life in prison.
Mr Costello’s skull was smashed in the attack and he was rushed to hospital with brain injuries but died two months later.
Appearing at Chester Crown Court, on Friday 17 November, Dunn was sentenced to a minimum term of 17 years and six months for the murder of Mr Costello.
The court heard Dunn had raised a number of complaints about Mr Costello, claiming he had broken the rules at the complex and was unhappy he had received a new car under the mobility scheme.
After finding a Z mark scratched into his new car, Mr Costello confronted Dunn, and Cheshire Police attended the scene and started an investigation.
The following day, Dunn took a spade from his neighbours shed and shortly before 10am, after Mr Costello's wife left their flat to take the dog on a walk, he entered and attacked Mr Costello.
Mr Costello was asleep on the sofa when Dunn hit him over the head three times with the side of the spade.
Dunn left the flat and disposed of the spade in a hedge before leaving the area on his electric scooter.
Mrs Costello returned at around 10am and found her husband with serious head injuries.
He was treated by paramedics before being taken to the Royal Stoke Hospital where he received emergency brain surgery.
He remained a patient for two months, until he died on 20 April.
Dunn was arrested the day of the incident and after Mr Costello's death, his charge was upgraded from section 18 assault to murder.
Detective Inspector David Hutcheon said: "Dunn’s actions that day were horrific. From the moment he awoke he was intent on causing harm to Mr Costello.
“He carefully planned his attack, hitting Mr Costello with a spade from behind as he slept on the sofa, knowing that he had no way to defend himself.
“During questioning Dunn admitted that he knew that he had inflicted serious injuries on Mr Costello following the first blow, but that he went on to hit him a further two times as he wanted to ‘teach him a lesson’.
“As a result of his actions that day, a wife has lost her loving husband, two children have lost their dad and six grandchildren have lost their caring granddad.
“While Mr Costello’s family will never be able to forget what happened that day, I hope that the fact that Dunn has now been held accountable for his actions and is likely spend a long time behind bars, will provide them with some closure.”
Sentencing Judge Steven Everett said: “You committed an appalling act of violence in a premeditated attack.
“He was asleep. He was totally defenceless and you took advantage of that in this cowardly attack. It was an act of incredible cowardice.
“Did you show any sympathy or compassion at that stage, did you call for an ambulance? Quite the reverse, you walked away showing no remorse as you threw away the spade and cycled to your former home.”
The judge said he continued to show “not a jot of remorse” when he was arrested and was “almost defiantly proud” when he confessed.
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