Gunshot residue was found on clothing taken from murder-accused Jay Dill the day after Randy Robinson was killed, Supreme Court heard yesterday.Mr Robinson, 22, was gunned down on March 31, 2011 while walking along Border Lane North in Devonshire, suffering a bullet wound to the chest and multiple shots to the head.Mr Dill, 23, and Devon Hewey, 24, have been charged with the premeditated murder of Mr Robinson and using a firearm to commit the offence. Both deny the charges.Prosecutors have alleged that Mr Dill was the gunman in the incident, opening fire from the pillion seat of a motorcycle ridden by Mr Hewey.Both men were arrested the next day in an early morning raid of Mr Hewey’s home.As their trial continued yesterday, gunshot residue (GSR) expert Alison Murtha testified that she tested samples taken from several items seized during the investigation into Mr Robinson’s murder.Ms Murtha explained that when a firearm is discharged, lead, barium and antimony are released into the air, typically dispersing up to five feet from the weapon. When the three elements fuse together, they form GSR.She said the presence of GSR is a clear indicator that the individual discharged a firearm, was near a firearm when it discharged or was exposed to something that was near a firearm when it was discharged.Ms Murtha also noted that any two of the component elements can fuse together when a weapon is discharged, but such compounds can also come from other sources such as fireworks, brake pad linings or airbag exhaust.Even in such cases, she noted that there are typically “elemental tags” which distinguish particles released by a gun shot and those caused by other sources, which are not included in particle counts.She said several GSR particles were discovered on a black jacket taken from Mr Dill at Hamilton Police Station the morning after the murder, including one on the front of the jacket, one on the left sleeve and two on the right sleeve.Another particle was discovered in the pockets of black jeans worn by Mr Dill.Particles containing two of the three components of GSR were found on both items, as well as Mr Dill’s motorcycle, the back of Mr Dill’s right hand and several seized items of clothing.Asked by prosecutors if the presence of GSR would be affected if a shooter fired from a motorcycle and then rode away, Ms Murtha said several factors could reduce the presence of GSR.“It’s outside in the elements,” she said. “If a bike is moving the force of air could be a factor, causing particles to be lost. It depends on the time before collection.”The trial continues.