The bullet which killed Charlie Kirk may not match up with the alleged assassin’s gun, according to suspect Tyler Robinson’s lawyers.Robinson, 22, is facing capital murder charges and a possible death sentence over the shooting at Utah Valley University on 10 September 2025.Prosecutors allege that he drove three hours to the campus to carry out the attack on the right-wing activist.In a recent court filing, however, the defence team have argued that the bullet recovered did not match up with the rifle tied to Robinson.The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) ‘was unable to identify the bullet recovered at autopsy to the rifle allegedly tied to Mr Robinson’, the defence say.Prosecutors, meanwhile, claim the Mauser model 98 gun had belonged to Robinson’s grandfather, who gave it to him as a gift.

The original Mausers were built to fire 8 mm cartridges, yet the recovered gun was a .30-06-calibre rifle.Zack Bonfilio, an expert, claims the bullets used in that type of rifle are difficult to match because they are designed to expand and break off upon impact, GB News has reported.The Independent reports that experts are looking for unique, microscopic marks left on the bullet as it passes through the barrel.Similarly, while prosecutors have argued that DNA consistent with Robinson was discovered on the rifle’s trigger, as well as the fired casing and two unfired cartridges, the defence has said forensic reports indicate that the DNA of numerous people had been found on a few items, and more testing was required.According to the filing, the FBI is also conducting further tests.Amid plans to present the analyst testimony to support Robinson’s innocence, the defence is requesting a delay of at least six months before the May preliminary hearing proceeds.