The Tulsa County Sheriff's Office will conduct an internal review of its deputy reserve program following national scrutiny of a 73-year-old volunteer who says he accidentally shot an unarmed suspect to death.

Spokesman Shannon Clark told the Tulsa World (http://bit.ly/1EIPaUE ) Thursday that there will be an audit, but didn't release other information.

Clark did not immediately return messages from The Associated Press seeking comment.

Reservist Robert Bates was charged Monday in the death of 44-year-old Eric Harris, who authorities say tried to sell guns to an officer. They say Bates accidentally shot Harris after confusing his stun gun and handgun.

Tulsa County employs about 130 reservists, who are given less training than regular deputies.