Okla. Stat. tit. 10, § 10-116b
Duties of probation officer - Investigations
It shall be the duty of the probation officer to perform any and
all duties required of him by the aforementioned judges of such
counties in the supervision, care, investigation, and rehabilitation
of persons whose sentences are suspended by the judges of the courts
of record of the county; and upon order of a district judge of such
county he shall investigate any matter pending before said judge and
report to him in the manner prescribed by said judge.