Damage to Sheffield grandfather Alan Greaves’ hat was consistent with the lay preacher having been beaten to death with a pick axe handle, a court heard.
Jurors in the trial of Ashley Foster yesterday heard from defence forensic scientist Gillian Leak.
Foster, aged 22, is accused - along with Jonathan Bowling - of attacking 68-year-old church organist Mr Greaves on Christmas Eve.
Foster, of Wesley Road, High Green, denies the killing - but Bowling, also 22, of Carwood Way, Pitsmoor, has admitted murder.
The prosecution say Foster and Bowling were both armed, and that both attacked Mr Greaves on Greengate Lane as he made his way to St Saviour’s Church for a midnight service.
But Foster says it was Bowling alone who attacked the pensioner, using a pick axe handle he’d hidden down his trousers.
Mrs Leak said she disagreed with prosecution forensic scientist Samantha Warner about how damage to Mr Greaves’ peaked cap was caused.
Ms Warner said she thought it was caused by a sharp weapon such as a claw hammer or a double ended crowbar, inflicted with such force the plastic interior had melted.
Mrs Leak said she agreed the force of the blow caused the plastic to melt, but in her opinion the damage was caused by ‘something linear with a curved edge’.
“The pick axe handle was the right general shape to have produced that impact,” she said.
Asked if she agreed the damage was caused by a bladed weapon, she said: “No.” She also disagreed with Ms Warner’s findings in relation to blood found on the park railings.
Mrs Leak said she thought some blood was exhaled by Mr Greaves, while the rest was ‘cast off’ spatter caused by him waving a blood-soaked glove.
Miss Warner said it was the result of a further blow to a bleeding wound.
The trial continues.