When transit systems experience delays, the reason usually isn’t very interesting: congested streets, medical emergencies, mechanical problems. But the cause of a recent holdup on San Francisco’s MUNI system at least had the virtue of being novel.

On Sept. 30 at around 11 p.m., an N Line streetcar ground to a halt at the intersection of Carl Street and Cole Street because an autonomous vehicle from Cruise, a subsidiary of General Motors, had halted on the streetcar tracks and wouldn’t budge. According to the city’s transportation department, the 140 passengers riding the N line that evening were stuck in place for seven minutes before a Cruise employee arrived and moved the driverless conveyance. (Cruise did not respond to questions about what happened that night.)

This incident, which was not reported in the media at the time, is one of many in which autonomous vehicles roaming San Francisco’s streets have disrupted the city’s transportation network. In April, a Cruise vehicle blocked a travel lane needed by a siren-blaring fire engine, delaying its arrival at a three-alarm fire. Last fall, dozens of self-driving cars from Google’s Waymo subsidiary drove daily into a quiet cul-de-sac before turning around, much to the frustration of nearby residents.

Because of California’s insufficient and outdated AV reporting requirements, many incidents like these have escaped both public attention and regulatory consequences. Facing minimal scrutiny, AV companies have little incentive to avoid mucking up the public right of way—or even keep city officials informed about what’s happening on their streets.

With Silicon Valley a few miles away, San Francisco has become the top urban location for AV testing and deployment. With California officials granting their first AV deployment permits allowing passenger service this year, the city now offers a preview of what’s to come in other places where self-driving companies are now fanning out, with expansions announced for Los Angeles, Las Vegas, Phoenix, and Austin.

Based on San Francisco’s experience, residents and officials in those cities should brace for strange, disruptive, and dangerous happenings on their streets. And they should demand that state officials offer the protection that California is failing to provide.

After a decade of testing and hype, it suddenly felt this year as if self-driving cars were everywhere in San Francisco. While individuals—in California or anywhere else—can’t buy these vehicles for themselves, companies are competing to improve the technology and roll out taxi services that resemble ride hail. In San Francisco, Cruise and Waymo allow residents to request a ride on their app, summoning a driverless vehicle that brings them to their destination. (Waymo transports passengers using safety drivers who can intervene if something goes wrong; Cruise does not.) Joining Cruise and Waymo robotaxis on San Francisco streets are testing vehicles from a number of other AV companies.

Two California agencies decide which autonomous companies have permission to operate within the state. The Department of Motor Vehicles issues permits for the vehicle itself (dozens of companies have obtained one), while the California Public Utilities Commission provides permits for passenger service. Earlier this year the CPUC issued Cruise and Waymo the state’s first robotaxi permits to transport paying passengers.

California requires that companies conducting AV testing submit information about collisions as well as “disengagements,” or moments when the autonomous system is forced to transfer driving responsibility to a human. The DMV publishes this information, along with each company’s total number of miles of autonomous driving on state roads. But AV executives—joined by some outside observers—have criticized disengagements as a deceptive metric, since it does not take into account the higher degree of difficulty navigating urban streets compared with interstates. Companies could also tinker with their disengagement data to seem safer than they are, something that the Chinese company AutoX has been accused of doing.

“It’s an open question whether or not disengagement data gives you anything useful,” said Billy Riggs, a professor at the University of San Francisco’s School of Management who has followed the state’s AV deployments closely. Even so, California’s regulatory focus on disengagements has powerfully shaped national media coverage of AV safety.

Strange as it may seem, California stops requiring that AV companies share disengagement data and collision locations as soon as they begin collecting passenger fares, as Waymo and Cruise now do. From that point forward, if an AV vehicle jeopardizes safety on the street—for instance, by causing a crash or blocking a transit line—the public won’t know unless the AV company chooses to publicize it (unlikely) or if a passerby reports the incident to 911 or posts about it on social media (unreliable).

Relaxing oversight for AVs with paying passengers might have seemed appropriate during the industry’s age of optimism several years ago, when policymakers could assume that companies would have “solved” autonomous driving before they started charging people for trips. If so, San Francisco’s experience shows that the reality is something else entirely.

Cities, for their part, play no defined role in the state’s AV regulatory structure, leaving them struggling to obtain information about AV-induced roadway blockages or even a list of companies deploying testing vehicles on their streets. Asked by email under what specific conditions Cruise notifies local leaders about an incident, spokesperson Hannah Lindow replied only that the company “maintains an open line of communication and meets regularly with city officials.”

Urban leaders anticipated these problems and tried to forestall them. In 2020 officials from Los Angeles, San Francisco, and San Diego asked the CPUC “not [to] create a deployment program that would give participants blanket authority to operate a fared service anywhere in the State.” The CPUC rejected that request, which has hobbled c