TransitCenter’s Director of Research Steven Higashide spoke on a keynote panel, “Autonomous Vehicles and Public Transit: A Threat Assessment,” at the North Carolina Public Transportation Association’s annual conference in April. This post is adapted from his remarks:

The threat that automated vehicles pose to public transit is a political threat. Pundits, politicians, and activists are now widely speculating that self-driving cars might “kill transit as we know it.” While some of these pronouncements are an honest attempt to account for the prospect of AVs in transportation planning, others are made in bad-faith – with real world consequences. Nashville’s transit referendum recently went down in flames, aided in at least some part by rhetoric from City Councilors proclaiming that Davidson County residents shouldn’t vote to invest in transit because “driverless buses will be ready in 12 months.”

In the midst of the hype, it’s essential for agencies to keep the following facts in mind (and up to advocates to remind them if they forget!):

High-capacity transit makes the most efficient use of scarce urban space, making cities more affordable and sustainable. According to the National Association of City Transportation Officials, a general-purpose traffic lane can carry up to 1,600 people per hour in cars – far fewer than the 4,000-8,000 people per hour that an on-street bus lane or the 10,000-25,000 people per hour in dedicated right-of-way for light rail or bus rapid transit.

In other words, even if some trips in autonomous vehicles are shared (and sharing won’t happen unless cities incentivize it) transit will always offer more capacity. Many current debates that try to cast Uber-type services as “on demand transit” obscure the reality that they are actually 21st Century taxis. That matters, because dense cities can’t function well without affordable ways to move scores of people through the congested, bottlenecked networks in and around them.

The adoption timeframe for AV technology is long and uncertain—and if “autonomy” is possible, will take the longest in urban neighborhoods. Automakers, investors, and developers of autonomous technology are increasingly warning that the rollout of automated vehicles will be slow and piecemeal. Shahin Farshchi, an investor in AV start-ups and sensor companies, tells WIRED that “autonomous technology is currently where computing was in the 60s.” The CEO of Argo AI (which received $1 billion from Ford to work on self-driving software) has written that “those who think self-driving cars will be ubiquitous on city streets … in a few years are not well connected to the state of the art or committed to the safe deployment of the technology.”

One thing that technologists agree on is that the hallmarks of driving in city neighborhoods – things like faded lane markings, children playing in the street, and people walking their dogs, not to mention bad weather — are much harder for computers to deal with than open highways. Even if we reach a point where automated vehicles can operate on highways or in specially planned developments, it will be longer until they might be capable of operating in the chaotic streetscapes of busy business districts and neighborhoods —the places where transit should be and often is the most concentrated.

When testing new technology, agencies and city leaders should be clear about their goals and how they are defining success. Transit agencies are already facing pressure to enter into partnerships with transportation network companies and launch “microtransit” pilots; autonomous vehicles may be next (in fact, small driverless shuttles are already being tested in Houston, Buffalo, and Atlanta).

But testing new technology for global motor vehicle markets for its own sake is a job for universities, research agencies, and private R&D; transit agencies that experiment need clear theories about what new services can accomplish – like improved access, increased ridership, or safer streets – and a plan to measure results against those goals. Having strong metrics related to what transit accomplishes (like the number of jobs reachable within a 30-minute transit trip) helps defend transit from political attack and helps staff think about how new technology might or might not add value. And let’s be clear: politicians are mainly inviting such tests to their cities to hitch themselves to the veneer of cool tech.

Transit systems need to make themselves more competitive now. Forget AVs—cities are already facing an explosion of new transportation technologies. In particular, the exponential growth of transportation network companies has had an impact on cities, adding a new choice for riders who can afford it, and adding substantially to city traffic congestion, which slows down buses.

It’s no coincidence that cities and agencies on the front line of the onslaught of TNC traffic—like San Francisco, Seattle, and now New York City—have recognized the importance of making comprehensive efforts to make local bus service faster, more frequent and reliable, and more legible for riders. Bus network redesigns (including bus stop balancing), transit-only lanes, transit signal priority, and all-door boarding need to be high on the agenda for transit agencies. Taking a user experience cue from ridesharing companies and making payment as simple as the click of a button or the tap of a card is also paramount.

On the other end of the spectrum, Pittsburgh is considering building more roads for the sake of running robot shuttles – while forcing its transit riders to fight tooth and nail just to preserve existing bus service. The shuttle project is projected to cost between 4 and 10 million dollars, money which could instead be used to eliminate the burdensome cost of transfers for today’s riders. In Las Vegas, bus ridership is falling but the Mayor is proclaiming Las Vegas to be a “global leader in innovation and sustainability” after launching an on-demand shuttle system designed primarily for tourists.

Failing to improve bus and rail service today means consigning city residents to slow and unreliable transit, or to a loan payment on cars they can barely afford. The 21st century challenges of growth, inequality, and climate change demand action now, not waiting for new technology that may arrive at some indeterminate point in the future.