California Code, Government Code - GOV § 11253

Upon written request approved by the Department of General Services, a department shall furnish to another department such assistance as it is able to render without detriment to its administration, including the deputizing of agents and inspectors, when consistent with law, and the temporary reassignment of employees.

Any traveling or other expense incurred by an employee in the performance of his duties while he is reassigned or loaned to another department may be paid in accordance with law by the department to which he is reassigned or loaned from funds available for support of that department.