California Code, Government Code - GOV § 1093

(a) The Treasurer and Controller, county and city officers, and their deputies and clerks shall not purchase or sell, or in any manner receive for their own or any other person's use or benefit any state, county or city warrants, scrip, orders, demands, claims, or other evidences of indebtedness against the state, or any county or city thereof.

(b) An individual shall not aid or abet the Treasurer, Controller, a county or city officer, or their deputy or clerk in violating subdivision (a).

(c) This section shall not apply to evidences of indebtedness issued to or held by an officer, deputy, or clerk for services rendered by them, nor to evidences of the funded indebtedness of the state, county, or city.