Okla. Stat. tit. 85, § 81
Each witness who appears in obedience to a subpoena before the Court to obtain the required information, shall receive for his attendance the fee and mileage provided for witnesses in civil cases.
Added by Laws 1915, HB 106, c. 246, art. 4, § 11; Amended by Laws 1977, HB 1228, c. 234, § 38, emerg. eff. July 1, 1978.