Reserve Deputy Who Says He Mistook Handgun for Stun Gun Gets 4 Years He killed a suspect who was restrained and unarmed By Newser Editors and Wire Services Posted May 31, 2016 6:55 PM CDT 103 comments Comments Robert Bates, 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, blows a kiss to family before his sentencing... (Sue Ogrocki) (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 sentenced Tuesday to four years in prison, the AP reports. A judge gave Robert Bates, 74, the maximum penalty recommended by jurors who last month convicted the wealthy insurance executive of second-degree manslaughter. Bates fatally shot Eric Harris while working with Tulsa County sheriff's deputies last year during an illegal gun sales sting. Harris, who had run from deputies, was restrained and unarmed when he was shot. After being sentenced, Bates was led away by deputies. His family members shouted, "We love you! We love you!" as he left court. Judge Bill Musseman said handing down the prison sentence was a "legitimate and moral consequence" of Bates' actions. He said he took into account Bates' failing health and dozens of letters written by members of the community asking for leniency from the court. Defense attorney Clark Brewster said they are planning an appeal. Bates' defense attorneys argued at trial that methamphetamine found in Harris' system, along with his cardiac health, caused his death. Defense attorneys called the killing 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.