In each county of this state having a population of one hundred ninety thousand (190,000) or more and containing a city of one hundred thousand (100,000) population or more, as shown by the last Federal Decennial Census or any future Federal Decennial Census, there is hereby created the office of probation officer, who shall be a county officer charged with the supervision and care of the parolees of such county, and who shall maintain an office in the county building of that county.
Okla. Stat. tit. 10, § 116