Okla. Stat. tit. 22, § 22-718: Witnesses - Fees and mileage

A witness who appears from another state to testify in this

state in a criminal case or proceeding pursuant to a subpoena issued

in accordance with the provisions of the Uniform Act to Secure the

Attendance of Witnesses from Without a State in Criminal

Proceedings, Section 721 et seq. of this title, shall be reimbursed

as prescribed by law for travel and expenses at rates not to exceed

those prescribed by law for reimbursement of state employees

traveling interstate. Such witnesses shall receive the same fees as

witnesses who appear from this state, pursuant to Section 81 of

Title 28 of the Oklahoma Statutes. If the witness is under eighteen

(18) years of age, or requires the assistance of a guardian due to

age or infirmity, the travel expenses of one parent or guardian may

be reimbursed also. The parent or guardian shall not be entitled to

a witness fee. Upon conviction, such fees and mileage shall be

taxed as costs, collected and deposited as other costs in the case.