Motor vehicle, 1; child-sized traffic calming sign, 0. Image by Chelsea Allinger. Used with permission.

Mayor Bowser is planning to triple the number of traffic cameras in the District. It’s not enough. We need even more automated enforcement. But the prevailing approach to ATE is over 50 years old. To do this fairly and effectively we need to try a new approach.

As our kids return to school, we are still grappling with a traffic safety crisis. Pedestrian and cyclist fatalities in the US reached an all-time high of 7,500 in 2022.

These national trends have been felt acutely in the Washington metropolitan area. Last year, our region experienced 141 pedestrian and cyclist fatalities – equivalent to the capacity of a Boeing 737. This was a 37% increase from 2021.

That is 141 neighbors lost, families shattered, and friendships disappeared, forever. Each and every incident is a tragic, personal story. These are more than mere statistics. And, of course, the human toll is much higher than the fatality numbers indicate. National data suggests that more than eight pedestrians are injured for every one killed.

We know that speed kills.

“A person hit by a car traveling at 35 mph is five times more likely to die than a person hit by a car traveling at 20 miles per hour,” says the National Association of City Transportation Officials. Both the Vision Zero movement and its federal counterpart, the National Roadway Safety Strategy, emphasize the need to control speed as a core pillar of a “safe systems approach” to traffic safety.

In the past few years, DC has taken action in this regard, lowering its default speed limit to 20 mph and passing a law that more consistently applies a 15 mph limit in school zones. However, neither street signage nor enforcement has kept pace with these changes. So they largely exist on paper only.

Compliance is the main challenge.

Our company, Passage Safety, recently conducted a speed study at three locations in Northeast DC. Over the course of 30 days in June and July our radar-equipped sensors continually measured vehicle speeds, clocking more than 315,000 vehicles in total. We found that approximately 70 percent of drivers exceeded the posted speed limit. Nearly 8,000 vehicles – about 260 per day, on average – exceeded the speed limit by more than 10 mph.

A Passage Speed Sensor mounted on a streetlight pole. Image credit: Passage Safety, used with permission.

The three locations were different in kind. One sensor was installed on a busy urban street, another on a notoriously fast minor arterial, and the third in a 15 mph school zone. The first location saw the slowest speeds overall, likely due to traffic congestion. The minor arterial, with a posted limit of 25 mph, saw the fastest speeds, with drivers frequently exceeding 40 mph and sometimes approaching 50 mph. Even though the school zone was measured about half a block beyond a stop sign, it experienced the highest proportion of speeding, with more than 94 percent of vehicles above the posted limit and about five percent of vehicles 10+ mph over the limit.

Speeding is a real issue. So, what’s the solution?

Architectural changes to roadway design may be the “gold standard” for addressing traffic safety challenges, where feasible. But any comprehensive and timely solution will also require a focus on behavioral reinforcement of safe driving habits.

Automated traffic enforcement (ATE) is an essential tool in this regard, but one that is overdue for rethinking from first principles. Misunderstood, often criticized, and sometimes even reviled, ATE is nevertheless enjoying a resurgence in the US. Mayor Bowser’s new budget, for example, will triple the number of speed cameras on DC streets. And with good reason: a study of DC’s ATE program showed significant and durable—albeit highly localized—reductions in speeding.

At the same time, the conventional approach to ATE suffers from some real limitations.

First, ATE tends to be too sparsely deployed to have a “global” effect on driving norms and habits. For example, DC is considered a leader in ATE deployments, having deployed about 132 ATE cameras. Yet the District has 13,754 city blocks! The ATE “coverage rate” is under one percent. Even if the city adds 342 cameras, as proposed in the Mayor’s budget, the coverage rate will still be under 3.5 percent. Put another way, 96.5 percent of city blocks will still lack enforcement.

Second, many people criticize the imposition of significant monetary fines on equity grounds, which some characterize as a regressive form of taxation. The placement of the cameras – which neighborhoods receive protection, which drivers are most closely monitored – is also a fraught question. It is important to note that both questions are intimately related to the first limitation–the scarcity of cameras–which inherently drives both a logic of high fines and raises hard choices about where to deploy them.

To her credit, Mayor Bowser recently established a Task Force on ATE Equity and Safety, with a charter to “mitigate against the potentially inequitable effects of the fine, penalty, and enforcement systems on individuals of varying household incomes while maintaining the public safety effectiveness of ATE and other moving violation programs.” The Task Force, composed of staff from across the District government, is due to release a report with actionable recommendations and pilot projects by October.

To drive meaningful change, we hope the Task Force will recognize that the current penalty system is not a bug, but rather a feature of ATE program design, rooted in criminological theory from the 1960s and ‘70s. The basic idea, familiar to economists everywhere, is the concept of “expected value.” When deployment of cameras is sparse, the probability of getting caught for speeding is low. Therefore, the way to deter “rational” drivers is to levy high fines. This theory has a satisfying logic and, furthermore, coheres with an assumption that sparse deployment is necessary due to the high cost of equipment.

Yet, what if both the behavioral theory and technological assumptions underpinning ATE are out of date? This is the central thesis we are pursuing at Passage, detailed in a white paper we submitted to the ATE Task Force.

It is time to transition from the “speed trap” model to a “safety zone” paradigm for ATE.

Technology advances now enable sophisticated traffic sensors to be built from commoditized, off-the-shelf components. These devices are compact and inexpensive. It is not unreasonable to expect that cities might be able to deploy ten or more next-generation sensors at the same cost as a single sensor today.

An abundance of sensors can “flip the script” for automated enforcement. Sensors could be deployed along entire corridors of neighborhoods facing safety problems. In place of infrequent enforcement and high fines we can move to a paradigm of widespread compliance with much smaller fines designed to “nudge” drivers to safer behaviors on a more continuous basis. For example, with 10 times more deployment we could replace the typical $100 fine with a more consistently applied $10 fine. We might even consider positive rewards for safe driving. For example, what if good drivers paid less for parking?

With fast wireless networks and cloud-based data processing we can alert drivers of speed infractions as they happen. In place of mailed citations that take weeks to arrive, drivers can receive near-real-time warnings on their phones – delivered via text message or audible app alerts – that change behavior “in the moment.” (Of course these mechanisms would have to be tested to avoid causing unsafe distractions.)

And, perhaps most importantly, with more data and a better driver feedback loop, we can conduct behaviorally-informed tests to devise compliance strategies that provide maximum safety benefit with minimal cost to drivers. We might replace one-size-fits-all enforcement with campaigns tailored to different kinds of traffic conditions. And we can better identify locations for which no amount of enforcement will solve the problem; where street design changes should be prioritized.

Put another way, new technology and new thinking promise a way out of the “more versus less” ATE policy debate. But for this generational shift to occur, America’s cities need to design their ATE strategies from a posture of innovation and experimentation. DC, under the leadership of Mayor Bowser, is in a position to invent the future of ATE. We hope it will seize this opportunity.