California Code, Government Code - GOV § 68543.5

(a) Whenever a judge who has retired under the Judges' Retirement System or the Judges' Retirement System II is assigned to serve in a court of record, the state shall pay the judge for each day of service in the court in the amount specified in Section 68543.7, without loss or interruption of retirement benefits, unless the judge waives compensation under this section. Whenever a retired judge of a justice court who is not a member of the Judges' Retirement System nor the Judges' Retirement System II is assigned to serve in a court of record, the state shall pay the judge for each day of service in the court in the amount specified in Section 68543.7, or the compensation specified in Section 68541, whichever is greater. The compensation shall be paid by the Judicial Council out of any appropriation for extra compensation of judges assigned by the Chairperson of the Judicial Council.

(b) If a judge who has retired under the Judges' Retirement System or the Judges' Retirement System II is assigned to serve in a court of record, the 8-percent difference between the compensation of the retired judge while so assigned and the compensation of a judge of the court to which the retired judge is assigned shall be paid to the Judges' Retirement Fund or the Judges' Retirement System II Fund, as applicable.

(c) During the period of assignment, a retired judge shall be allowed expenses for travel, board, and lodging incurred in the discharge of the assignment. When assigned to sit in the county in which he or she resides, the judge shall be allowed expenses for travel and board incurred in the discharge of the assignment. The expenses for travel, board, and lodging shall be paid by the state under the rules adopted by the Department of General Services that are applicable to officers of the state provided for in Article VI of the California Constitution while traveling on official state business.

(d) Notwithstanding subdivisions (a), (b), and (c) pertaining to compensation, a retired judge on senior judge status shall receive compensation from the state as provided in Sections 75028 and 75028.2, and shall be allowed expenses for travel, board, and lodging incurred in the discharge of the assignment as provided in this section.