Street Illegal: A Hot Take on Hot Cars

Noise camera technology, or automated noise enforcement (ANE), is now used widely around the world — in New York City, Chicago, California, Canada, London (UK), Paris (France), Berlin (Germany) and The Netherlands, among others — to automatically ticket noisy cars and motorcycles. Why bother, what is ANE and is it relevant here in the Twin Cities?

As I’ll explain later, this issue interests me personally, given that I live just west of St. Paul’s Cretin Avenue, which has become something of an urban highway and threatens to grow even more crowded in the coming years, and near Mississippi River Boulevard and Marshall Avenue, both popular drag strips for joy riders.

Why Worry About Noise?

The scientific community and World Health Organization (WHO) increasingly recognize noise, and specifically traffic noise, as an important public health threat. 

As an internist and University of Minnesota professor of medicine and environmental health, I’m concerned by the multiple harmful health effects of traffic noise.

Noise’s population-level health impact is huge. For example, the WHO estimates that annually in western Europe — where the issue has been studied most — the number of years of full-quality life lost due to noise is 587,000 for annoyance, 22,000 for hearing disturbance, 903,000 for sleep disturbance, 61,000 for cardiovascular disease and 45,000 for cognitive impairment in children. Children from low socio-economic backgrounds, who have higher environmental noise exposure, may be especially affected.

Noise exposure is typically expressed as the average noise level, in decibels (dB) (see schematic above), or time above a certain level. However, intermittent traffic noise — e.g., from revving and backfiring — may be as or more harmful (Barcelona, Switzerland). This is highly relevant to the noisy vehicle problem, which I discuss below.

The adverse health effects of traffic noise likely result, in part, from physiological responses such as the release of stress hormones (e.g., adrenaline and cortisol), a heightened oxidative state and activation of the sympathetic nervous system. These responses increase heart rate, cardiac contractility, blood pressure and blood clotting tendency.

Traffic noise also harms the community overall. For example, in one study noise annoyance was associated with less social cohesion and a lower perceived psychologically restorative quality of the neighborhood, and thereby with less physical activity and worse mental health. Noisy vehicles can disrupt the environment and people’s peaceful enjoyment of their homes and public places. Providence, Rhode Island Mayor Brett Smiley pursued ANE after receiving numerous noise complaints. “Part of the reason people like to live in Providence is the quality of life, and it’s important that we not lose that,” he told a reporter.

Why Pick on Noisy Vehicles?

Traffic noise, a longstanding problem, results from the routine use of gasoline or diesel-powered vehicles — with their noisy engines, horns, brakes, tires and loads — to move people and objects from place to place. 

What’s new is a proliferation of extra-noisy cars and motorcycles that are inherently loud due to souped-up engines and less-muffled exhaust systems (see images and videos), and are often driven aggressively, maximizing noise output.

Such noise-making can be deliberate. In a survey-based study from London, Ontario, noisy car fans tended to be young males who scored high for sadistic and psychopathic tendencies. Online comments by noisy car owners reflect delight in their vehicle’s loudness (Providence, Rhode Island; New York City video comments). I’ve observed noisy vehicles behaving maliciously toward pedestrians, such as pulling up quietly and suddenly emitting loud roars, in one instance with a large windshield decal that said: “Annoying.”

Self-indulgent, antisocial noise production affects me intensely, from both the noise per se and the associated sense of threat, victimhood, lawlessness and disempowerment, which inspire fear, withdrawal and anger. I grow hyper-alert and tense, anticipating the next sonic assault.

Don’t We Have Noise Limits?

Legal vehicle noise limits typically are based on subjective criteria and/or dB thresholds (see below Minnesota Pollution Control Agency [MPCA] graph of dB limits for cars). Drivers of noisy vehicles flout such limits with impunity. Enforcement is difficult using conventional approaches — having police officers pull over and ticket excessively noisy cars, as they do for speeders — because excessive vehicle noise is unpredictable, brief and widely distributed. Noisy vehicles are usually gone by the time officers respond to a complaint. Traffic stops also risk biased enforcement and tragic driver-officer interactions. Intensified manual enforcement is possible, but attention is turning increasingly to ANE.

What Is ANE?

ANE uses an array of computer-linked microphones for noise detection and video cameras for vehicle identification. Such systems typically monitor sound continuously, recording video data only if noise levels exceed a threshold, such as 85 dB. If computer-assisted data analysis confirms a violation, the vehicle is identified by its license plate number, and a ticket is mailed to the registered owner; otherwise, the data is discarded.

ANE’s advantages include that it captures infrequent events through continuous monitoring, avoids subjectivity/bias and relieves officers. In Amsterdam, “The new system of automatic fines will make noise infringements much easier to police than is currently the case,” according to Amsterdam’s traffic chief Egbert de Vries.

ANE’s disadvantages include its start-up cost (which, however, the resulting fines may exceed), fixed locations (which can result in gapped coverage) and difficulty capturing motorcycle license plates. Additionally, ANE risks (mis-)perceptions of privacy violation (“Big Brother” data collection) and racial/class bias, by ostensibly either targeting poor non-whites (Amsellem, Providence) or denying them the technology’s benefits (Providence). Fixed-amount tickets also disproportionately affect the poor, although most noisy vehicle owners do not seem poor (given their costly vehicles), and other cities have used economic justice measures to protect the poor from burdensome fines.

Do We Need ANE?

My neighborhood has a noisy vehicle problem. For example, during 17 hours of observation in September 2024, I recorded more than 37 bothersome noise events (over 2.2 per hour), mainly engine revving and backfiring, from my home near Dayton Avenue and Exeter Place in St. Paul. (Many more occurred, but were too closely spaced to be counted.) St. Paul’s noise ordinances prohibit “use (of) any…vehicle which causes…significant discomfort or annoyance…due to loud, disturbing or excessive noise”, and “discharge…of any…motor vehicle…except through a muffler…that effectively prevents loud or explosive noise“; therefore, I observed multiple violations. Additionally, of 12 neighbors whom I queried about noisy vehicles, two expressed mild dislike, whereas 10 expressed moderate to extreme dislike. 

Supporting these subjective impressions were phone app-based dB measurements I made on September 8, 50 feet from the Cretin-Selby intersection. During one hour I noted six spikes to > 80 dB (i.e., 83, 85, 87, 91, 92, 95 dB), whereas the legal limit (per Minnesota statutes) is 75 dB (see above MPCA graph). Similarly, when walking along Mississippi River Boulevard I’ve noted multiple spikes into the 90s, with peaks of 104 dB.

That said, in my one-question survey of 30 community festival attendees in Merriam Park on September 22, vehicle noise was nobody’s top transportation-related concern. Likewise, although multiple members of St. Paul’s Union Park District Council Transportation Committee (on which I serve) shared my noisy vehicle concerns, several were more bothered by freeway noise from Interstate 94, engine braking, banging loads or loud recorded music.

Collectively, these observations indicate a noisy vehicle problem that is abundant and bothersome, even if not most people’s No. 1 transportation-related concern or noise issue. Given the inefficacy of manual enforcement, ANE warrants consideration.

Could We Get ANE?

Minnesota cities presumably could implement ANE, provided that any legal barriers were resolved, funding was identified, logistical issues were overcome, and community concerns about privacy, fairness and bias were addressed. Back-of-the-envelope calculations suggest that ticket revenues could easily exceed system costs ($20,000 to $35,000 per detector, plus operating costs). Ironically, in other communities this has prompted accusations that ANE is just a revenue-generating ploy. Detectors ideally would be placed where needed most according to noise maps (rather than complaint numbers) and context. That could mean, for example, prioritizing schools, hospitals, parks and residential areas.

Local leaders interested in ANE could confer with their counterparts in cities where ANE is already used. Our leaders, however, are unlikely to act without a compelling reason, such as advocacy from their constituents. For example, the relevant St. Paul Public Works staffer told me that they would not pursue ANE without encouragement from elected officials.

In turn, via email and at a Transportation Committee meeting, St. Paul City Council President Mitra Jalali (who is also my councilmember) suggested that Public Works might take the lead. She expressed concerns regarding ANE’s supposed technical limitations and privacy issues, plus the expectation that vehicle noise could be addressed by combating speed and focusing manual enforcement on “hot spots” — all of which reflect a limited understanding of the situation.

In a follow-up conversation with Jalali’s chief legislative aide, Doua Yang, I learned that Jalali also questions the extent of the problem: Is it (or are concerns about it) limited to privileged neighborhoods such as mine? She’s unaware of concerns from other District Councils, Yang said.

What Can a Concerned Citizen Do?

• Tell your city council member and mayor that vehicle noise is important to you and your community, due to its adverse effects on physical and mental health, quality of life and societal harmony. 
• Ask them to ensure that existing vehicle noise ordinances get enforced.
• Ask specifically that ANE receive serious consideration.
• Talk to your friends and neighbors about noise and encourage their advocacy.