Okla. Stat. tit. 12, § 12-400: Witness may demand fees each day - Exception

At the commencement of each day after the first day, a witness

may demand his fees for that day's attendance in obedience to a

subpoena; and if the same be not paid, he shall not be required to

remain, except witnesses subpoenaed by any state department, board,

commission or legislative committee authorized by law to issue

subpoenas shall be paid for their attendance and necessary travel as

provided by law in other cases at the time their testimony is

completed.