Driverless cars sound less and less like science fiction with each passing month, and that’s prompted widespread discussion about how they might change society. They will bring many changes, but when it comes to the car’s role in the city, they may just intensify current tensions.

The Atlantic Cities’ Emily Badger interviewed a research team of computer scientists at the University of Texas at Austin, who studied how to make intersections move far more cars than they can today. They devised algorithms that let cars flow through the intersection without need for lights that only let one direction of traffic move at a time.

But what’s missing from this diagram? How about… people?

Badger writes,

[H]uman-driven cars would have to wait for a signal that would be optimized based on what everyone else is doing. And the same would be true of pedestrians and bike riders.

That certainly sounds like all other users of the road will have to act at the convenience of the driverless cars, under constraints designed to maximize vehicle movement instead of balance the needs of various users.

My background is in computer science, too, and computer scientists love figuring out how to make complex systems perform efficiently. Driverless cars provide an opportunity to optimize the real-world traffic system, if you can get most people driving computer-controlled cars and can get all of those computers to cooperate.

But you can’t optimize people so easily. Already, cities host ongoing and raucous debates over the role of cars versus people on their streets. For over 50 years, traffic engineers with the same dreams about optimizing whizzing cars have designed and redesigned intersections to move more and more vehicles.

These changes frequently pushed other users aside with longer waits for crosswalks, the need to push buttons to get a walk signal, awkward bridges over wider and wider arterials, or simply omitting bike or pedestrian facilities entirely and then blaming those users when careless drivers hit and kill them.

Some pro-automotive advocacy groups like to push the theme of a “war on cars,” but bicyclists and pedestrians feel like there’s been a war against them since the early 20th century. This Texas team’s video just perpetuates that impression.

The video even depicts an intersection with a whopping 12 lanes for each roadway, at a time when most transportation professionals have come to believe that grids of smaller roads, not mega-arterials, are the best approach to mobility in metropolitan areas.

Driverless cars, therefore, are poised to trigger a whole new round of pressure to further redesign intersections for the throughput of vehicles above all else. It won’t only happen in the cities, either. Suburban areas are often ground zero for these debates, where the majority of people drive, but a significant and often growing number are either unable to drive due to age or disabilities, or are unable to afford cars. (Driverless cars probably won’t be cheaper.)

Suburbs, therefore, often develop a greater tyranny of the majority, where county and state departments of transportation optimize their roadways for car throughput and leave bus stops in awkward and narrow roadside spots, leave crosswalks out or even remove existing ones, and set the stage for rising deaths.

If autonomous cars travel much faster than today’s cars and operate closer to other vehicles and obstacles, as we see in the Texas team’s simulation, then they may well kill more pedestrians. Or, perhaps the computers controlling them will respond so quickly that they can avoid hitting any pedestrian, even one who steps out in front of a car.

In that case, we might see a small number of people taking advantage of that to cross through traffic, knowing the cars can’t kill him. That will slow the cars down, and their drivers will start lobbying for even greater restrictions on pedestrians, like fences preventing midblock crossings.

Our metropolitan areas could then look, more and more, like zoos for humans interlaced with pathways for the dominant species, the robot car. Maybe the machines really are on the way to taking over, but instead of Skynet declaring war on humans, we’ll be the ones passing laws and reshaping our communities for their convenience.

I’m not suggesting we avoid research into driverless cars. Like any technology, they can bring good or evil, depending how society handles them. Driverless cars can allow buses to become on-demand jitneys and virtually eliminate the need to own a personal car in a city, or to build huge amounts of parking under office buildings. Instead of storing cars during the day, they can just drive around and transport people like taxis.

But we do need researchers excited about driverless cars not to forget the human element. The goal of our built environment is not to move cars as fast as possible everywhere, but to create a better quality of life. The computer science researchers need to also talk to their colleagues in other disciplines, set appropriate goals that consider all users of the roads, and think about what algorithms can actually make life better.

Cross-posted at The Atlantic Cities.

David Alpert created Greater Greater Washington in 2008 and was its executive director until 2020. He formerly worked in tech and has lived in the Boston, San Francisco Bay, and New York metro areas in addition to Washington, DC. He lives with his wife and two children in Dupont Circle.