Shots fired but no gunpowder residue?

I'm not particularity knowledgeable on this subject and was hoping some here might be able to explain.

Police officers won't face charges in fatal shooting of protester Manuel Teran at Atlanta's 'Cop City'

Quote:

According to an autopsy of Teran sent to ABC News, they did not have gunpowder residue on their hands. Officials claimed Teran fired the first shot at a state trooper. Officers then responded with gunfire. Friday's announcement that no charges would be filed, Christian wrote that Teran responded to officers firing "less lethal" pepperball rounds by "shooting four (4) times his 9 mm pistol through the tent striking and seriously injuring a Georgia State Trooper. Six Troopers returned fire resulting in the death of Teran."

So my question is how do you shoot a 9mm 4 times but the autopsy shows no gunpowder residue?

via International Skeptics Forum https://ift.tt/o2Um4Ne