San Diego County, CA Public Conduct: Loud Party Ordinance (2026)

303(a). Reasonable steps specifically listed include controlling access to alcohol and marijuana, checking every attendee's government ID, and actively supervising minors present. 303(b) to let the party continue once the host knows, or reasonably should know, that a minor has obtained, possessed, or is using alcohol or marijuana there, even if the host took some precautions initially. 304 creates a rebuttable presumption: if the person controlling the property is simply present when a minor drinks or uses marijuana at the gathering, the law presumes the host knew or should have known.

301, cite excessive noise disturbance, physical altercations, vandalism, and diverted law enforcement resources as the harms this chapter targets, and note the County is not reimbursed for responding to these calls, which is the ordinance's practical hook for cost recovery. Narrow exceptions exist: a parent or legal guardian may serve alcohol to a minor under their own supervision at a family gathering, and religious ceremonies are exempt, but medical marijuana use by a minor authorized under state law is also carved out. 307 makes a violator liable to the County, beyond criminal prosecution, for the actual cost of the enforcement services the incident required, including officer salaries, medical costs, and property damage repair. 305.