Cal. Government Code § 68097.4

Any member of the California Highway Patrol who is obliged to appear pursuant to a subpoena issued under the provisions of Section 68097.3 as a witness, shall receive from the State the salary or other compensation to which he is normally entitled as a member of the patrol during the time that he travels to and from the place where the court is located and while he is required to remain at such place pursuant to such subpoena. He shall also receive from the State the actual necessary and reasonable traveling expenses incurred by him in complying with such subpoena. The party at whose request a subpoena is issued pursuant to Section 68097.3 shall reimburse the State for the amount of the salary or other compensation to which the member of the California Highway Patrol involved is normally entitled from the State during the time that he travels to and from the place where the court is located and while he is required to remain at such place pursuant to such subpoena; and in addition, such party shall reimburse the State for the actual, necessary and reasonable traveling expenses incurred by the member of the California Highway Patrol in complying with such subpoena. An amount equal to the estimated amount of such salary or other compensation and expenses shall be deposited with the clerk of the court prior to the issuance of such subpoena. If the actual amount of such salary or other compensation and expenses should later prove to be more than the amount deposited, the party shall also deposit the difference with the clerk. If the actual amount should later prove to be less than the amount deposited, the excess of the amount deposited shall be refunded. All amounts received by the clerk to which the State is entitled shall be remitted to the Department of the California Highway Patrol for deposit in the State Treasury.