DECATUR, Ga. (AP) — A DeKalb County commissioner has resigned from her post amid a federal probe into questionable spending.

Commissioner Elaine Boyer, who has been in office for more than 20 years, told WSB-TV on Monday she betrayed constituents and abused her position.

An investigation by WSB-TV and the Atlanta Journal-Constitution highlighted $16,000 in personal purchases Boyer made with her county debit card. The television station reported that Boyer had already repaid about half the charges before the investigation began, and has since repaid all of the money.

The Atlanta Journal-Constitution reports a continued examination of Boyer's spending raised additional questions on her purchases.

Before her resignation, Boyer told WSB-TV she was unaware what she was doing was wrong, despite having signed an agreement saying purchase cards couldn't be used for personal expenses.