A forensics expert told a jury that a shotgun used to shoot dead Marion Millican could not have been accidentally fired during a struggle.
Fred McClenaghan (52), of Broad Street, Magherafelt, is on trial accused of murdering the mother-of-four at a Portstewart launderette in March 2011.
On the opening day of his trial last week he entered a plea of guilty to manslaughter which was rejected by the prosecution who said it was “murder, pure and simple”.
The defendant claims he accidentally shot Mrs Millican during a struggle when he alleges she grabbed the shotgun.
Giving evidence at Antrim Crown Court, sitting in Belfast, the forensics expert said she tested the 100-year-old, 12-bore double barrelled shotgun in a number of scenarios.
The witness said she found that the trigger mechanism on the shotgun was “functional”, despite its age.
The court heard that during testing at the Northern Ireland Forensic science laboratory, she demonstrated to the court that she dropped the shotgun onto its butt from three different heights, ranging from 15 centimetres to 45 centrimetres, to see if would accidentally fire.
“From these three depths there was no discharge. The hammers remained in the cocked position,” she told the jury sitting with trial judge Mr Justice Treacy.
The forensics expert said that she also used a wooden mallet to hit the cocked hammers to see if it would make them move. “The hammers remained in the cocked postion,” she said.
The witness also told the jury that she attached a metal line to trigger mechanism and suspended weights from the rod to see which weight would release the cocked hammers.
“I found that the weight required for the trigger mechanism to initiate the hammer was a weight of four-and-a-half pounds on the right barrel and a weight of five-and-a-half pounds on the left barrel.”
She said that she also carried out what she described as a “belt and braces test” to see if the gun could be discharged during a struggle.
The witness told prosecution counsel Neill Connor: “It was part of ad hoc exercise to see if the barrels could be reached from a certain distance during an alleged struggle.
“The gun was held at waste height by my colleague, shooting from his hip.”
But she said that gun was not fired during the re-enactment of the struggle and “the hammers remained cocked back.”
She added that it was her view that the gun could have not been discharged accidentally during a struggle and the only way the rounds could be fired was by pulling the trigger.
The forensics expert said that she also test fired the shotgun at various distances of range, from close up to further away, to ascertain the extent of the impact on a target caused by a shotgun cartridge.
She added that she did this after examining the deceased’s clothing and also post mortem pictures to see if the shotgun round had left any residue or black markings on her body or outer clothing.
“My professional opinion was that the gun was fired at no more than three feet from the target but was more likely to have been fired at from one to two feet,” the expert told the jury.
“There was no evidence to support the view that there was very close contact between the gun and the victim.”
The witness added that she found nothing to support the view that “the deceased was holding the barrels at the time the gun was discharged”.