Okla. Stat. tit. 22, § 151
There is no limitation of the time within which a prosecution for murder must be commenced. It may be commenced at any time after the death of the person killed.
R.L. 1910, § 5624; Amended by Laws 1935, HB 165, p. 20, § 1, emerg. eff. May 2, 1935; Amended by Laws 1943, SB 79, p. 84, § 1, emerg. eff. April 12, 1943.