Forensic experts uncovered bullet cartridge residue in an alleged killer's pocket, a murder trial heard yesterday.
Giving evidence at the Belfast Crown Court diplock trial of 41-year-old James Edward Taylor and Richard Harkness, Mrs Anne McLeod-Irwin said that in the pocket of a jacket seized from Taylor, she found "two unique particles of CDR" and that due to their components, they would have come from a cartridge.
She told prosecuting QC Gordon Kerr that her findings "supports an association with this item and a source of CDR".
The court has already heard that both Taylor and Harkness were arrested on September 29 2004 in the hours after Darren Thompson was shot and killed in the Woodburn Park area of Londonderry.
Acting under a warrant issued under the terrorism act, police were already searching Taylor's house at nearby Lincoln Court in Londonderry at the time of the killing and he was arrested when he came home that morning.
Taylor was placed in a forensic cape with officers also covering his hands and feet with evidence bags for later examination after they were swabbed.
Under cross-examination by Taylor's defence QC Billy McCrory, Mrs McLeod-Irwin agreed that no CDR was found on other parts of his clothing or on the swabs taken from his hands, face and head hair.
She further agreed she could not tell how long the CDR had been in the jacket pocket and added that if a person had fired a gun or been close to a gun being fired, "I would expect to find residues on the outer surface as well".
The scientist said she had found CDR on six spent .38 bullet casings police found in a safe in Taylor's house and agreed with the suggestion that the CDR in the jacket pocket could have come from the shells.
The trial has also heard that a T-shirt and a pair of jeans were seized from Harkness and also tested for CDR.
Under cross-examination by his defence QC John McCrudden, Mrs McLeod-Irwin told the court there was no CDR found on the swabs taken from his hands, on his clothing or inside his Citroen Xsara car.
Trial judge Mr Justice Treacy also heard from forensic firearm expert Leo Rossi yesterday, who examined the bullet taken from Mr Thompson's head and the six spent cases found in Taylor's house.
He told the court that the "very badly impact damaged" bullet taken from Mr Thompson "may have originated from one of the cases" but later agreed with Mr McCrory that "you cannot reach any forensic conclusions as to whether the firearm that discharged with shells was the same firearm that discharged the bullet".
The lawyer further suggested to Mr Rossi that he could show no connection between the shells and the bullet with the scientist agreeing, "not as such".
Taylor and Harkness, from Baranailt Road in Claudy, both deny murdering Mr Thompson.