In this screen shot from April 2, 2015 video provided by the Tulsa County Sheriff's Office, police restrain 44-year-old Eric Harris after he was chased down and tackled by a Tulsa County Deputy, and then shot by a reserve sheriff's deputy while in custody, in Tulsa, Okla. The sheriff's office said 73-year-old reserve deputy Robert Charles Bates fired the shot that killed Harris, believing he was using his stun gun instead of his service weapon when he opened fire. (AP Photo/Tulsa County Sheriff's Office)

A reserve deputy who fatally shot a man during an undercover drug sting was charged with second-degree manslaughter Monday, according to a press release from the Tulsa County district attorney's office.

“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,’” District Attorney Steve Kunzweiler said in the press release.

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

Read: Statement from Eric Harris' family