Okla. Stat. tit. 69 § 619
The boards of county commissioners of the several counties of the state shall have authority to receive by agreement with the governing board of any municipality, the prisoners of the municipality, who have been sentenced to imprisonment in the municipality's jail, either as punishment or in lieu of payment of fine and costs for the violation of any municipal ordinance, and such board of county commissioners shall have authority to work any such prisoners on the public highways or upon a rock pile, or rock crusher, for the purpose of providing material for use upon public highways or any public institution of such county, or upon any public work in which the county is interested. Any such person so imprisoned for nonpayment of fine and costs shall receive credit upon his or her fine and costs of One Dollar ($1.00) for each day so confined in prison or worked upon the public highways, rock pile,
rock crusher, or other public work; provided, the board of county commissioners shall not pay for the services of such prisoners, except the cost of their transportation and maintenance.
Okla. Stat. tit. 69, § 619