Opinion | June 26, 2023

Conor Semler is a Principal Planner in Kittelson’s Boston office. Conor has been working in the transportation profession since 2007 and has a wide range of experience partnering with public agencies to address transportation challenges, with a focus on improving conditions for walking and bicycling through better evaluation and design. This article represents Conor’s views on this topic and is meant to inspire thought and discussion within the profession.

We can all relate to the frustration and fear of seeing a driver speed recklessly down our street. In an instant, the sense of safety we all want to feel in our neighborhoods and workplaces is put at risk.

The reason we’re afraid is we know the damage speeding can do. We hear statistics like the national average of traffic deaths dramatically increased in 2020 and 2021, and held steady in 2022 at around 40,000. Speeding is conservatively estimated to be a factor in 1/3 of all traffic fatalities (though given how common speeding occurs, it’s likely much higher). We’re talking more than 10,000 deaths every year associated with speeding.

Speeding is conservatively estimated to be a factor in 1/3 of all traffic fatalities, though given how common speeding occurs, it’s likely much higher.

Keenly aware of this crisis, transportation agencies are investing significant time, effort, and money into implementing Vision Zero and road safety plans, with a focus on reducing speeds through traffic calming measures. These efforts are very important, but very costly—and we’re facing a long, slow trajectory to get those tragic statistics to budge.

With millions of dollars spent every year on projects specifically designed to limit speeding, we’ve established that reducing speeding is a priority worth investing in. Why not also use existing technology to limit speeding in a much simpler, and potentially more affordable and effective way?

I care deeply about tackling our country’s road safety crisis, and I’ve spent a lot of time thinking about and researching the potential of using speed limiters in cars to automate adherence to posted speed limits. This article summarizes what I’ve found and contemplated to date. This topic might make you excited, or it might make you stiffen—whichever boat you’re in, I’m interested in hearing your perspectives so we can make these ideas stronger, and develop something that will finally put a big dent in the massive, heartbreaking numbers I shared above.

With millions of dollars spent every year on projects specifically designed to limit speeding, we've established that reducing speeding is a priority worth investing in. Why not also use existing technology to limit speeding in a much simpler, and potentially more affordable and effective way?

The Technology Behind Speed Limiters in Cars

Through advancements in vehicle technology, cars will now intervene when a driver’s behavior isn’t sufficient. Cars that are equipped with advanced sensors will beep frenetically when traveling too fast toward an obstacle in the road, and brake when the driver fails to do so. My family’s car has saved me from backing into my recycling bin on more than one occasion, and the technology has saved lives in more serious situations, like conflicts with pedestrians in parking lots and sudden braking situations on freeways.

In addition, newer cars “know” the posted speed limit of the road they’re traveling on. I recently learned that our car (which was produced in 2021) can be programmed to beep a warning every time I exceed the speed limit.

We’re missing an opportunity to combine advancements in vehicle technology with the ability of newer cars to identify the road they’re on and the speed limit of that road. The technology exists today to automatically cap a driver’s speed based on the speed limit of the road on which the car is traveling.

The idea of a speed cap is actually nothing new. All cars have built-in speed caps (i.e., governor devices); they’re just usually set very high, and don’t change based on context. We trust drivers to choose the right speed within the large range they’re given, paying attention to road signs and other context clues. But as we’ve seen, drivers abuse that privilege—over and over and over again.

What Would It Look Like to Govern Speeds in Cars?

A subtle version of this idea is programming cars to alert drivers every time they exceed the speed limit. Essentially, the technology that already exists in my car would no longer be optional. At the risk of being annoying to drivers, this action would serve to reinforce their awareness of speeds at all times, and hopefully get them to question whether or not they need to be driving over the posted speed. These same measures are taken to encourage drivers to wear their seatbelts (even though this is already the law).

To take full advantage of technology’s ability to help us travel more safely, however, we can take the concept a step further: cars could be programmed to not allow the driver to drive above the posted speed limit. This would mean cars automatically comply with the law, and would make driving a car more similar to the experience of taking a bus, train, or some other mode in which you don’t have the ability to make the vehicle move faster. And it has the potential to achieve a dramatic reduction in roadway injuries and deaths. If drivers simply aren’t allowed to speed, we could prevent thousands of deaths every year on our roads. Is that a tradeoff worth making?

If drivers simply aren’t allowed to speed, we could prevent thousands of deaths every year on our roads.

The “What Ifs”

I’ve thought about this concept long enough that I know there are legitimate questions that come along with it. For example, what about situations in which going 5-10 mph above the speed limit can generally be done safely (such as on a freeway, where everyone is traveling in the same direction)? Is limiting a driver’s speed in this situation unnecessarily restrictive?

I welcome dialogue on this question, but my view is if it’s deemed safe for people to exceed a posted speed limit, then we should adjust the speed limit to the tolerable number, rather than relying on driver judgment to determine the situations in which speeding is acceptable.

Perhaps the most pervasive argument against automatic speed limiters is fear around emergency scenarios. What about a situation in which I need to go faster? What if I’m running late to an important appointment? What if the situation is truly an emergency, like driving my injured child to the hospital?

My response to this question is threefold. Firstly, it is very reasonable that emergency vehicles should be able to drive over the speed limit to save lives. If you have the option, calling an ambulance is the safest way to get you or your loved one the expedient care you need. Secondly, as frustrating as it is, there are plenty of other things outside of your control that could inhibit your ability to drive quickly in those situations. What if it’s snowing, or you’re in heavy traffic? We simply don’t have full control, even though sitting behind the wheel gives us the illusion we do. Finally, I think the most compelling argument is this: by planning for “what if” scenarios, which are more the exception than the rule, we’re allowing far more roadway deaths every day than lives we’re saving.

We simply don’t have full control, even though sitting behind the wheel gives us the illusion we do.

The idea of an external force inhibiting my freedom as a driver can be uncomfortable. I get it. But I think society as a whole has gotten too comfortable with breaking the law while driving. Speeding is breaking the law, even though it isn’t often talked about that way. And it’s not restricting freedom to prevent people from doing illegal things. For example, we put locks on our doors even though it’s illegal to break into homes.

When seatbelt laws were established, they were met with significant resistance in the name of losing personal liberties. Change is hard, particularly when it involves limiting a behavior that was previously tolerated. However, in the ~40 years since New York was the first state to require the use of seatbelts, seatbelt laws have become mainstream and are rarely questioned, having been credited with saving millions of lives.

I’ll also offer this point: statistics show that Americans tend to overestimate their own driving abilities. Even if we agree that speeding is a societal issue, as individuals, we tend to think we are personally savvy enough to speed safely and appropriately… until we realize the hard way that we’re not.

Cars Are Not an Exception

We’ve gotten used to seeing speed limits as mere suggestions when driving. However, this same logic isn’t applied to other forms of transportation, such as e-scooters (which are being capped in many places at 10 mph) and bikeshare. I was recently in Denver for the NACTO conference and riding bikeshare past their baseball stadium during a game. My bike automatically slowed as I entered the blocks around the stadium where speed restrictions were instituted. The problem was I was riding in a street with traffic, and the cars around me were not speed restricted! If we’re applying these tactics to bikes and scooters, it’s important that cars (which are at a much higher risk of seriously hurting people) are included as well.

Okay, But How Could We Practically Roll This Out?

Outside of the concerns I listed above, perhaps the biggest barrier to implementing speed limiting technology is the practicality of rolling it out. Even if the technology exists to automate compliance with speed limits, we can’t just snap our fingers and make it so, particularly because most cars on our roads today don’t have the technology built in.

This is where we need to think creatively and collaboratively as a profession, because we’ve solved this dilemma before and I believe we can do it again. Here are some ideas I’ll offer:

1. We could start by following Europe’s example and simply making the technology present in new cars being manufactured, even if we’re not ready to “turn it on” yet. A New York state lawmaker is attempting to do this very thing through supporting a bill that would require cars made in 2024 and beyond to be equipped with “intelligent speed assistance” technology. This step would mirror the evolution of seatbelt laws, which were nationally mandated to be installed more than 20 years before it became law that people wear them.

2. How can we incentivize people to retrofit their vehicles with this technology? I propose starting with ride hailing companies: requiring all Uber, Lyft, and other ride hailing vehicles to start using the technology in exchange for something that would motivate them.

3. Let’s think about which industries would monetarily gain from safer streets. For me, the insurance industry comes to mind. Auto insurers could give massive incentives to people who install this in their vehicles, and in return, the vehicles they’re insuring will operate more safely.

Let’s Talk About This!

Everything in our profession comes down to tradeoffs, and I think it’s worth thinking long and hard about whether the loss of some freedom and control behind the wheel is worth the outcome of preventing thousands of deaths on US roads every year. My review leads me to believe that speed limiting technology could help us achieve a dramatic reduction in roadway deaths in a short amount of time, and at a low cost relative to the money we’re investing in traffic calming measures.

But as I shared at the outset of this article, this idea needs further dialogue and perspectives. Where and how do you see this working, and what additional concerns do we need to think about? I would love to hear your questions, doubts, and suggestions, and invite you to email me directly or comment on our LinkedIn thread on the topic. Ultimately, we’re all trying to solve the same issue, and I hope we can work together to find a solution that works better than what we’re doing now.