Okla. Stat. tit. 57, § 528.5

A. The Department of Corrections is authorized to reimburse an employee of the Department of Corrections for any cost associated with initially obtaining or renewing a commercial driver license, if a commercial driver license is necessary for that employee's performance of official duties for the Department of Corrections. B. Any employee who has received reimbursement pursuant to subsection A of this section may be required to reimburse the Department of Corrections a prorated amount of the cost of the commercial driver license upon leaving the employment of the Department of Corrections.