Chapter 10.64 — SOCIAL HOST ORDINANCE

This chapter is entitled and shall be known as the "Social Host Ordinance." (Ord. 2257 NCS §1, 2006.)

A. The city council of the city of Petaluma, pursuant to the city’s police powers under Article XI, Sections 3 and 5

of the California Constitution, and the City Charter established pursuant to such sections, has the authority to

enact and enforce laws that promote the public health, safety and general welfare of its residents. The occurrence

of social gatherings on private property where alcoholic beverages are served to, or consumed by, underage

The Petaluma Municipal Code is current through Ordinance 2916 NCS, passed December 1, 2025.

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persons is harmful to the underage persons involved and a threat to public health and safety, quiet enjoyment of

residential property and the general welfare. Underage persons often obtain alcoholic beverages at gatherings

held at private residences or at rented residential and commercial premises that are under the control of a person

who knows, or should know, of the underage consumption of alcohol.

B. The city council Mnds that in too many cases, persons having possession or control of private property who

are responsible for social gatherings on that property have failed to ensure that alcoholic beverages are neither

served to, nor consumed by, underage persons at these gatherings. The city council further Mnds that problems

associated with social gatherings where alcoholic beverages are served to, or consumed by, underage persons are

diOcult to prevent and deter unless the Petaluma police department has the legal authority to direct the host to

disperse the gathering and to cite the responsible persons.

C. Law enforcement personnel have in the past been required to respond to unruly gatherings on private

property at which alcoholic beverages are served to, or consumed by, underage persons. Law enforcement

personnel have also received multiple service calls in the same calendar year concerning unruly gatherings at the

same property. Such calls for service result in a disproportionate expenditure of public safety resources and delay

oOcial responses to other calls in the rest of the city. Additionally, underage drinking at such gatherings has

resulted in disproportionately higher numbers of underage persons driving while intoxicated, increased social

violence, and incidents of sexual assault.

D. An ordinance that imposes liability on property owners and other responsible persons for gatherings that

allow underage drinking is necessary to deter and prevent such gatherings. Persons who actively and passively aid,

allow, or tolerate such gatherings should be held liable for permitting such gatherings, the nuisances created by

them and the costs associated with responding to them.

E. The purposes of this chapter include: protecting the public health, safety and welfare by deterring the service

to and consumption of alcoholic beverages by underage persons, and reducing the costs to the public of providing

police response services to unruly gatherings and gatherings of underage persons where alcohol is served, both in

terms of monetary costs and availability of law enforcement personnel for other calls. These purposes are

implemented by the imposition of criminal penalties for social hosts as well as the imposition of administrative

penalties for social hosts and landowners (including landlords) and the imposition of fees to recover the costs

incurred by the city in providing law enforcement responses to gatherings where alcoholic beverages are served

to, or consumed by, underage persons at properties where previous such gatherings have required law

enforcement responses.

F. For these reasons, the Petaluma city council declares that gatherings on private property where alcoholic

beverages are served to, or consumed by, underage persons are a threat to the public peace, health, safety and

general welfare, and a public nuisance as they aPect at the same time the entire Petaluma community as well as

the neighborhoods in which they occur.

(Ord. 2257 NCS §1, 2006.)

The Petaluma Municipal Code is current through Ordinance 2916 NCS, passed December 1, 2025.

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For the purposes of this chapter, the following deMnitions shall apply:

A. "Alcohol." The deMnition of "alcohol" in Section 23003 of the California Business and Professions Code, as

amended from time to time, shall apply to this chapter. As of the introduction of this chapter, Section 23003

deMned "alcohol" to mean "ethyl alcohol, hydrated oxide of ethyl, or spirits of wine, from whatever source or by

whatever process produced."

B. "Alcoholic beverage." The deMnition of "alcoholic beverage" in Section 23004 of the California Business and

Professions Code, as amended from time to time, shall apply to this chapter. As of the introduction of this chapter,

Section 23004 deMned "alcoholic beverage" to mean "alcoholic beverage includes alcohol, spirits, liquor, wine,

beer, and that contains one-half of one percent or more alcohol by volume and that is Mt for beverage purposes

either alone or when diluted, mixed or combined with other substances."

C. "City" means the city of Petaluma.

D. "Juvenile" means any person under eighteen years of age.

E. "Response costs" means the costs associated with responses by law enforcement to unruly and underage

gatherings including but not limited to:

1. Salaries and beneMts of law enforcement personnel for the amount of time spent responding to,

remaining at, or otherwise dealing with unruly or underage gatherings, and the administrative costs

attributable to such response(s);

2. The cost of any medical treatment to or for any law enforcement personnel injured responding to,

remaining at or leaving the scene of an unruly or underage gathering;

3. The cost of repairing any city equipment or property damage, and the cost of the use of any such

equipment, in responding to, remaining at or leaving the scene of on unruly or underage gathering; and

4. Any costs recoverable in accordance with California Civil Code Section 1714.9.

F. "Responsible person" means a person or persons with a right of possession of the residence or other private

property in the city at which an underage or unruly gathering may occur, including, but not limited to, the

following:

1. Any owner of the residence or other private property, meaning the record owner of the title to property

as of the time of the underage or unruly gathering, wheresoever that person or entity may currently reside;

2. A tenant or lessee of the residence or other private property;

3. The person(s) exercising control over the residence or other private property at the time of the underage

or unruly gathering; and

The Petaluma Municipal Code is current through Ordinance 2916 NCS, passed December 1, 2025.

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4. The person(s) who organizes, supervises, oOciates, conducts or controls the underage or unruly

gathering or any other person(s) accepting responsibility for such gathering. A responsible person for the

underage or unruly gathering need not be present at such gathering.

G. "Underage gathering" means a party or gathering of two or more persons at a residence or other private

property in the city at which alcoholic beverages are being consumed by any underage person.

H. "Underage person" means any person under twenty-one years of age.

I. "Unruly gathering" means a party or gathering of two or more persons at a residence or other private

property in the city at which alcoholic beverages are being consumed by any underage person when that party or

gathering is being conducted in such a manner as to constitute a substantial disturbance of the quiet enjoyment of

private or public property in a signiMcant segment of a neighborhood, as a result of conduct constituting a

violation of law. Such conduct constituting a violation of law for purposes of this deMnition includes, but is not

limited to: excessive noise, excessive traOc, obstruction of public streets by crowds or vehicles, public

drunkenness or unlawful public consumption of alcohol or alcoholic beverages, assaults, batteries, Mghts,

domestic violence or other disturbances of the peace, vandalism, littering, and any other conduct that constitutes

a threat to public health, safety, quiet enjoyment of residential property or general welfare.

(Ord. 2257 NCS §1, 2006.)

It is the duty of responsible persons to not knowingly host, permit, or allow an underage or unruly gathering at a

residence or other private property in the city concerning which the responsible person has a right of possession

speciMed in Section 10.64.030(F) and to take all reasonable steps to prevent the consumption of alcoholic

beverages by any underage person at gatherings at such residence or other private property. Reasonable steps

required pursuant to this section include, but are not limited to: controlling access to alcoholic beverages at the

gathering; controlling the quantity of alcoholic beverages present at the gathering; verifying the age of persons

attending the gathering by inspecting drivers’ licenses or other government-issued identiMcation cards to ensure

that underage persons do not consume alcoholic beverages while at the gathering; and supervising the activities

of underage persons at the gathering. (Ord. 2257 NCS §1, 2006.)

It is unlawful and a public nuisance for any responsible persons to knowingly host, permit, or allow an underage or

unruly gathering to occur at private property in the city concerning which the responsible person has a right of

possession speciMed in Section 10.64.030(F) where at least one underage person consumes an alcoholic beverage.

For purposes of this chapter, a responsible person knowingly hosts, permits or allows an underage or unruly

gathering where at least one underage person consumes an alcoholic beverage whenever the responsible person

is aware an underage person has consumed an alcoholic beverage at an underage or unruly gathering or

The Petaluma Municipal Code is current through Ordinance 2916 NCS, passed December 1, 2025.

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reasonably should have been aware an underage person has consumed an alcoholic beverage at such a gathering

had the responsible person taken all reasonable steps to prevent consumption of alcoholic beverages by

underage persons in accordance with Section 10.64.040. Violation of this section by any responsible person is

subject to the criminal, civil and/or administrative penalties set forth in this chapter in addition to recovery of

response costs in accordance with Section 10.64.110, and any other applicable penalties under applicable law. It

shall be prima facie evidence that the responsible person knew or should have known of both the underage or

unruly gathering and the consumption of alcoholic beverages by underage persons at the gathering if the

responsible person is present on the property at any point during the gathering. To the full extent permitted by

law, owners of properties as deMned in Section 10.64.030(F)(1) shall remain responsible persons liable for

violations of this chapter on such property regardless of any contract or agreement regarding the property that

purports to provide otherwise. (Ord. 2257 NCS §1, 2006.)

This chapter does not apply to conduct involving the use of alcoholic beverages that is protected by Article I,

Section 4 of the California Constitution. (Ord. 2257 NCS §1, 2006.)

In the event that a juvenile hosts an unruly or underage gathering at a residence or other private property in the

city in violation of this chapter, the parents or guardians of that juvenile will be jointly and severally liable for any

penalties and response costs imposed pursuant to this chapter. (Ord. 2257 NCS §1, 2006.)

Violations of this chapter may be prosecuted as misdemeanors punishable by a Mne of not more than one

thousand dollars or by imprisonment for a period not to exceed six months, or by both Mne and imprisonment. At

the discretion of the charging oOcer and/or city attorney, violations of this chapter may also be charged as

infractions as deMned in Section 19(c) of the California Penal Code. Violations charged as infractions shall not be

subject to imprisonment and shall be subject to a Mne not exceeding Mve hundred dollars for each oPense. If a

police oOcer elects to charge a violation of this chapter as a criminal violation, such oOcer shall issue a criminal

citation with a notice to appear, signed by the alleged violator. Alternatively, the city attorney may prosecute

violations of this chapter by Mling a criminal complaint. (Ord. 2257 NCS §1, 2006.)

The Petaluma Municipal Code is current through Ordinance 2916 NCS, passed December 1, 2025.

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violations.

Violations of this chapter are declared to be public nuisances. Violations of this chapter may be prosecuted as a

nuisance and enforced by a civil court action as provided in Chapter 1.13 or via administrative enforcement as a

nuisance as provided in Chapter 1.14. Notwithstanding any other provisions of this chapter, whenever the

existence or continuance of any violation of this chapter or any nuisance condition poses an imminent or

immediate threat of harm to persons or property, or to public health, welfare or safety, such violation or condition

may be summarily abated in accordance with Section 1.15.010. Each and every day during any portion of which a

nuisance condition exists or continues may be deemed a separate and distinct violation for purposes of setting

the amount of penalty to be imposed. Any penalty imposed will accrue on a daily basis from the date the penalty

becomes ePective. (Ord. 2257 NCS §1, 2006.)

In addition to the other remedies speciMed in this chapter, violations of this chapter are subject to the

enforcement remedies in Chapters 1.10 through 1.12 and 1.15. In addition, the city expressly reserves the right to

utilize enforcement remedies available under any applicable state or federal statute or pursuant to any other

lawful power of the city. All such remedies shall be alternative to or in addition to or in conjunction with, and not

exclusive of, one another. The election of remedies shall be at the sole discretion of the city. (Ord. 2257 NCS §1,

2006.)

When the police make an initial response to an underage or unruly gathering at a residence or other private

property within the city, and a police oOcer issues a citation for violation of this chapter, the oOcer shall, in

writing, inform any responsible person(s) at the property that:

A. An unruly or underage gathering exists; and

B. The responsible person(s) will be charged for any response costs incurred for subsequent responses to the

property for an underage or unruly gathering within a twelve-month period.

This warning will be given to all identiMed responsible persons at the time of the Mrst response to an unruly or

underage gathering where a citation is issued for violation of this chapter before assessing response costs

pursuant to this section for subsequent responses within a twelve-month period following issuance of the citation.

Within thirty calendar days of the initial citation, an additional written warning shall be transmitted via certiMed

mail to the record owner of the residence or private property as shown in the records of the Sonoma County

Assessor’s oOce.

The Petaluma Municipal Code is current through Ordinance 2916 NCS, passed December 1, 2025.

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When a police oOcer responds to an underage or unruly gathering at a residence or other private property within

the city within twelve months of a citation and warning given to responsible person(s) at the same property, and

such oOcer issues a second or subsequent citation pursuant to this chapter, all responsible persons shall be

jointly and severally liable for the city’s response costs concerning such second or subsequent underage or unruly

gathering, but only to the extent that such responsible person(s) concerning the Mrst citation at such property

remain responsible person(s) for the second or subsequent citation at such property.

(Ord. 2257 NCS §1, 2006.)

Any administrative penalty imposed for violation of this chapter, including any administrative penalties pursuant

to other codes or statutes to which violations of this chapter are subject, and any administrative costs or other

expenses of enforcement, response costs as deMned in this chapter, and the cost or expenses associated with the

abatement of a nuisance condition pursuant to this chapter, may be enforced by the recordation of a lien or

special assessment on the real property where the violation occurred in accordance with and subject to the

requirements of Section 1.14.140. (Ord. 2257 NCS §1, 2006.)

A responsible person charged with violation of this chapter pursuant to Chapter 1.14 shall be entitled to pursue

the appeal procedures set forth in Section 1.14.070 for responsible persons named in notices of violations. (Ord.

2257 NCS §1, 2006.)

This chapter is not intended to impose, and shall not be construed or given ePect in a manner that imposes upon

the city, or any oOcer, employee, agent, or representative of the city, a mandatory duty of care toward persons or

property within or without the city limits, so as to provide a basis of civil liability for damages, except as may

otherwise be imposed by law. (Ord. 2257 NCS §1, 2006.)

The Petaluma Municipal Code is current through Ordinance 2916 NCS, passed December 1, 2025.

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