California Code, Public Contract Code - PCC § 6101

(a) A state agency, as defined in Section 10335.7, that is subject to this code, shall not award a public works or purchase contract to a bidder or contractor, nor shall a bidder or contractor be eligible to bid for or receive a public works or purchase contract, who has, in the preceding five years, been convicted of violating a state or federal law respecting the employment of undocumented immigrants.

(b) For purposes of this section, “immigrant” means a person who is not a citizen or national of the United States.