Foley says the prosecutor received nearly $5,000 in improper expense payments between 2008 and 2010.
The state auditor says Tingelhoff was reimbursed for returned items and sometimes reimbursed twice for the same items.
Tingelhoff says he has fixed the accounting problems the auditor found and reimbursed the county nearly five grand.
Among one of the auditor's larger complaints: Tingelhoff spent more than $3,400 of grant money on seven flat-screen televisions in 2009.
When the audit was finished this March, five of the TVs were still in their boxes and one had been returned.
Tingelhoff defended the purchase.
He says the TVs are now being used to review video evidence in his office and in court.
Tingelhoff says the audit inspired new policies.
All of the office's expense reports now must be accompanied original receipts instead of copies, and the person preparing the report has to sign them so they can be tracked.