Okla. Stat. tit. 52, § 52-100: Witnesses - Depositions

The Commission may cause depositions of witnesses residing

within or without the state to be taken in any proceeding pending

before it in any manner provided by law for taking depositions in

civil actions in courts of record; and any deposition so taken shall

be sealed up and endorsed with the title of the cause and the name

of the officer taking the same, and by him addressed and transmitted

to the Secretary of the Commission, where it shall remain under seal

until opened by the Secretary on order of the Commission, or at the

request of a party to the proceeding, or an attorney for such party.