Okla. Stat. tit. 19, § 19-215.13: Grand jury

Whenever required by the grand jury, it shall be the duty of the

district attorney of the district or his assistant or assistants, to

attend them for the purpose of examining witnesses in their presence

or of giving them advice in any legal matter, and to issue subpoenas

and other process to enforce the attendance of witnesses, and to

draw up bills or indictments when found by such grand jury. The

district attorney is authorized to issue subpoenas upon his own

motion during the grand jury for the purpose of examining witnesses

in the presence of the grand jury and the district attorney is

further authorized to issue subpoenas upon his own motion for the

purpose of examining witnesses before a grand jury that is to be

called within ninety days from the issuance of said subpoenas. If,

for any reason, the district attorney and all of his assistants are

disqualified to act in a particular matter being investigated by the

grand jury, the Attorney General of Oklahoma shall appoint one or

more Assistant Attorney(s) General or a district attorney or

assistant district attorney from another district to act in such

matter, as provided in Section 215.9 of this title.