Reserve Deputy Convicted for Accidentally Shooting Suspect He's facing four years in prison for manslaughter By Newser Editors and Wire Services Posted Apr 27, 2016 6:45 PM CDT 67 comments Comments Robert Bates arrives for his arraignment at the Tulsa County courthouse in 2015. (AP Photo/Sue Ogrocki, File) (Newser) – A former Oklahoma volunteer sheriff's deputy who said he mistook his handgun for his stun gun when he fatally shot an unarmed suspect last year was convicted of second-degree manslaughter on Wednesday, the AP reports. Robert Bates, a wealthy 74-year-old insurance executive, was accused of fatally shooting Eric Harris while working with sheriff's deputies during an illegal gun sales sting last year. Harris, who had run from deputies, was restrained and unarmed when he was shot. The shooting—which was caught on video—sparked several investigations that, among other things, revealed an internal 2009 memo questioning Bates' qualifications as a volunteer deputy and showed that Bates, a close friend of the sheriff's, had donated thousands of dollars in cash, vehicles and equipment to the agency. Bates now faces up to four years in prison. His defense attorneys argued at trial that methamphetamine found in Harris' system, along with his cardiac health, caused his death, which they called an "excusable homicide." But prosecutors told jurors that Bates was guilty of culpable negligence when he shot Harris. One deputy testified that Bates apparently dozed off minutes before Harris fled from deputies. Weeks after Harris was killed, an internal sheriff's office memo from 2009 was released by an attorney for Harris' family that alleged superiors knew Bates didn't have enough training but pressured others to look the other way because of his relationship with the sheriff and the agency. Sheriff Stanley Glanz resigned Nov. 1 after being indicted by a grand jury.