Cupertino, CA Public Conduct: Loud Party Ordinance (2026)

48 Community Noise Control definition. 020, makes it unlawful and a public nuisance to host an Event on Property, which includes homes, apartments, hotel or motel rooms, and rented commercial premises, where alcohol or a controlled substance is served to, consumed by, made available to, or possessed by a minor or underage person. A Social Host is broadly defined: the person who owns, rents, leases, or controls the premises; anyone present during the Event; anyone in charge of the premises; or anyone who organized or advertised it.

If a Minor Social Host is involved, that minor's parents or guardians are jointly and severally liable regardless of whether they knew about the gathering. 030 makes a violation a civil infraction enforced by the Santa Clara County Sheriff or the City's code enforcement officers: adult hosts and parents of minor hosts get a written warning and cease-and-desist notice for a first offense, a fine up to $500 for a second violation within a year, and up to $1,000 for a third or later violation in that year.

Minor Social Hosts themselves must complete a Sheriff-approved alcohol and drug abuse prevention course after a first violation, 25 hours of community service for a second violation within a year, and 40 hours for a third or subsequent violation. 040 makes these remedies cumulative, so the City can still pursue any other civil or criminal remedy available under state law.