California Code, Elections Code - ELEC § 18390

An agency or department of the state shall not use its publications to advise state employees of a constitutional officer's choice of candidates for public office or for recommending positions on specific ballot propositions not related to the functions of that agency or department.

For purposes of this section “publications” means any written or printed matter including, but not limited to, agency or department memorandums or directives, but shall not include legislative newsletters or state voter information guides.

A state officer who violates this section is guilty of a misdemeanor.