Education Code § 39834

(a) Except as provided in subdivision (b), any officer, agent, or employee of a school district, office of the county superintendent of schools, or joint powers agency, or any other person, knowingly operating, or permitting or directing the operation of a schoolbus, when it is loaded with schoolchildren in excess of the limits of its seating capacity, is guilty of a misdemeanor.

(b) The governing board of any school district, office of the county superintendent of schools, or joint powers agency may adopt a district policy establishing plans for the evacuation of pupils in case of any emergency that may provide, where necessary, for the loading of schoolchildren on a schoolbus in excess of the limits of its seating capacity.

(c) As used in this section, “emergency” means a natural disaster or hazard that requires pupils to be moved immediately in order to ensure their safety.