Resources

What these sources document. California Vehicle Code section 21 bars a city from enforcing its own ordinance on any matter the Vehicle Code covers unless the code expressly authorizes it, and no authorization exists for vehicle noise. The city's own ledger productions list 814 citations under section 10.28.007, the city's general nuisance noise ordinance, from 2021 through September 22, 2026. The city's own hearing officer wrote that the argument these citations are preempted "may be true" and that a correct ruling "would invalidate the entirety" of the program. The full case, in order, is on the main page. If you received one of these citations, you have 21 days from service to contest it.

Every source cited on this site, in one place. Everything here is either an official public source or a document produced by the City of Newport Beach under the California Public Records Act.

State law

• California Vehicle Code section 21. The preemption rule: the Vehicle Code is uniform statewide, and local authorities may not enact or enforce ordinances on matters it covers.
• Vehicle Code section 27150. The muffler requirement: adequate muffler preventing "any excessive or unusual noise."
• Vehicle Code section 27151. Modified exhaust, with the objective compliance standard in subsection (b): 95 dBA or less under the SAE test.
• Vehicle Code section 27150.2. The State Referee sound test for cited vehicles.
• Vehicle Code section 27150.7. Grounds for dismissal on a certificate of compliance or a reasonable-grounds belief the exhaust was compliant.
• Government Code section 53069.4. The appeal route: 20 days from service of the decision to Superior Court, de novo review.
• Government Code section 70615. The $25 filing fee for that appeal.

Case law

• Pipoly v. Benson (1942) 20 Cal.2d 366. Field preemption of local road-use regulation.
• Rumford v. City of Berkeley (1982) 31 Cal.3d 545. Section 21 as the state's preemption of the entire field of traffic control.
• O'Connell v. City of Stockton (2007) 41 Cal.4th 1061. A city vehicle ordinance struck under section 21 absent express authorization.
• People v. McNeil (2002) 96 Cal.App.4th 1302. The preemption line reaffirmed.
• Haas v. County of San Bernardino (2002) 27 Cal.4th 1017. Due process condemns the risk of bias when an adjudicator's future income depends on the good will of the frequent litigant paying the fee. The structural problem with city-contracted hearing officers.

Newport Beach Municipal Code

• NBMC Chapter 10.28, Loud and Unreasonable Noise. Contains section 10.28.007, the section these citations are written under.
• NBMC Chapter 10.26, Community Noise Control. The city's quantitative noise code, including the section 10.26.035(H) preemption exemption. PDF copy.
• NBMC Chapter 1.05, Administrative Code Enforcement Program. The citation, deposit, hearing, and decision procedures. PDF copy.

Enforcement guidance and records

• The hearing decision in the author's case (PDF, redacted for personal information). The city's Findings of Fact and Statement of Decision upholding the citation while stating the preemption argument "may be true," that a correct ruling "would invalidate the entirety of the City's regulation as to noise emanating from vehicles," and that the question belongs to a court. Hosted in full so every quote on this site can be checked against its source.
• CHP Information Bulletin No. 98-100 (transcription). The CHP's guidance that local vehicle noise ordinances are not authorized and citations under them "are invalid." The transcription notes its sourcing and corrections. No official copy appears on CHP's public website.
• The March 6, 2026 hearing decision that overturned a vehicle noise citation (PDF, redacted for personal information). Administrative citation ADM24419D, in which the hearing officer agreed that an officer's subjective judgment "is not viable to sustain the citation" for a stock vehicle and overturned it for insufficient evidence. The appellant also raised state preemption, which the officer did not reach. The same hearing officer later wrote, in the author's case, that the preemption argument "may be true." Hosted in full.
• The City of Newport Beach citation ledgers (one through July 10, 2026, and one for citations issued July 11 through September 22, 2026) and hearing decisions cited on this site were produced under the California Public Records Act in 2026. They are public records: anyone can request them from the City Clerk.
• CBS Detroit: Royal Oak, Michigan throws out 130+ engine-revving tickets after determining its local ordinance conflicted with state law.
• Newport Beach Police Department, March 12, 2026 post. The department's own account of the February operation: 196 citations, 100 administrative, 11 State Referee referrals. A capture is in the data section.
• City of Newport Beach video post. Body-worn camera footage of one of these stops, published by the city's own account, captioned "Leave the unnecessary revving in the desert." Preserved copy, also embedded in the data section.
• NBPD video post, August 2026, captioned "By enforcing laws against loud exhaust and street racing, we aim to create a safer environment for everyone in our community." Preserved copy, also embedded in the data section.
• City of Newport Beach, 2021 press release. The city's own description of joint operations with the DMV and Bureau of Automotive Repair: 649 stops, 500 Vehicle Code citations, 72 on-site BAR Referee inspections. The lawful route, run by this city, before the municipal program scaled.
• The city's public records portal. Where the records requests behind this site were filed, and where anyone can file their own.

Tools on this site

• The document generator. Produces your hearing request, records request, and evidence submission from your details, entirely in your browser.
• Blank templates. The same three documents with bracketed fields.
• The step-by-step guide. Deadlines, procedure, and what to argue.

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