California Code, Vehicle Code - VEH § 15620

(a) A parent, legal guardian, or other person responsible for a child who is 6 years of age or younger may not leave that child inside a motor vehicle without being subject to the supervision of a person who is 12 years of age or older, under either of the following circumstances:

(b) A violation of subdivision (a) is an infraction punishable by a fine of one hundred dollars ($100), except that the court may reduce or waive the fine if the defendant establishes to the satisfaction of the court that he or she is economically disadvantaged and the court, instead, refers the defendant to a community education program that includes education on the dangers of leaving young children unattended in motor vehicles, and provides certification of completion of that program. Upon completion of that program, the defendant shall provide that certification to the court. The court may, at its discretion, require any defendant described in this section to attend an education program on the dangers of leaving young children unattended in motor vehicles.

(c) Nothing in this section shall preclude prosecution under both this section and Section 192 of the Penal Code, or Section 273a of that code, or any other provision of law.