Okla. Stat. tit. 21, § 21-854: Proof of marriage - Wife as competent witness - Duty of

County Attorney to prosecute.

No other evidence shall be required to prove marriage of such

husband and wife, or that such person is the lawful father or mother

of such child or children than is or shall be required to prove such

fact in a civil action, and such wife shall be a competent witness

to testify in any case brought under this act, and to any and all

matters relevant thereto, including the fact of such marriage and

the parentage of such child or children. It shall be the mandatory

duty of each district attorney of this state to diligently prosecute

all persons violating any of the provisions of this chapter (Chapter

31, Title 21 O.S.1951), and in all cases where the evidence is

deemed sufficient to justify a prosecution for such violation, any

district attorney who shall willfully fail, neglect or refuse to

institute criminal proceedings to enforce such provisions, shall be

subject to removal from office.