Okla. Stat. tit. 22, § 22-495: Witnesses on hearing to set aside indictment or

information.

All witnesses, including grand jurors, shall be bound to answer

fully, and shall not be answerable for the testimony so given in any

way, except for the crime of perjury committed in giving such

evidence. When a grand juror has been fully examined as to his

qualifications to sit, and has answered under oath that he is

qualified, and has been received by the court and permitted to act,

his incompetency shall not thereafter be shown as a ground of

objection to any indictment returned by that grand jury.