Oklahoma Reserve Deputy, 73, Charged With Second-Degree Manslaughter in Stun-Gun Mix-Up: Tulsa DA

— -- The 73-year-old volunteer reserve deputy in Oklahoma who fatally shot a suspect in an incident that the Tulsa County Sheriff's Office called "inadvertent" has now been charged with second-degree manslaughter, the Tulsa County District Attorney's Office said today.

Reserve deputy Robert Bates shot and killed Eric Harris April 2 after the deputy allegedly mistook his handgun for a stun-gun, officials said.

"Mr. Bates is charged with Second-Degree Manslaughter involving culpable negligence. Oklahoma law defines culpable negligence as ‘the omission to do something which a reasonably careful person would do, or the lack of the usual ordinary care and caution in the performance of an act usually and ordinarily exercised by a person under similar circumstances and conditions,'” Tulsa County District Attorney Steve Kunzweiler said in a statement today.

"The defendant is presumed to be innocent under the law but we will be prepared to present evidence at future court hearings."

After viewing video of the shooting, a Tulsa Sheriff's Office spokesman told ABC News earlier today, "You can tell it was inadvertent. The gun popped out of his [Bates] hand. He wasn't expecting a recoil," Maj. Shannon Clark added.

Bates, an unpaid volunteer who worked on a violent crimes task force and had to maintain firearm proficiency, "never intended in his 73 years of life to take a human life," Clark said. "No one intended for Mr. Harris to die that day."

ABC News has been unable to reach Bates, and a message left at his daughter’s home has not been returned.

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