Okla. Stat. tit. 43, § 43-10: Evidence before issue of license

If the judge or clerk of the district court before whom

application for a marriage license is made shall be in doubt of the

legal capacity of the parties for whose marriage a license is

sought, to enter into the marriage relation, such judge or clerk

shall require additional evidence to that contained in the

application, and may swear and examine witnesses or require

affidavits in proof of the legality of such marriage, and unless

satisfied of the legality thereof, he shall not issue a license

therefor.