Okla. Stat. tit. 22, § 22-494

To enable the defendant to make proof of the matter set up as

grounds for setting aside the indictment, or information, the

defendant may file his application before any court of record in the

county, setting out and alleging that he is being proceeded against

in a certain court, naming it, and setting out a copy of his motion

and alleging, all under oath, that he is acting in good faith, and

praying for an order to examine witnesses in support thereof. The

court shall thereupon issue subpoenas to compel any or all witnesses

desired to appear before him at the time named, and shall compel the

witnesses to testify fully in regard to the matter and reduce the

examination to writing, and certify to the same, and it may be used

to support the motion. The mover shall pay the costs of the

proceeding. He shall notify the district attorney at least two

clear days before he proceeds, of the time and place of taking such

testimony, and the district attorney may be present and cross-

examine the witnesses and if need be the case in the district court

must be adjourned for that purpose.

R.L. 1910, § 5781.