NEW STUDY: Robotaxis in New York City Could Spike Congestion and Have Limited Safety Benefits
New York, NY—Robotaxis in New York City would unleash more empty miles of traffic and may result in more serious crashes than professional for-hire vehicle drivers, according to a groundbreaking report released today by the Sam Schwartz Transportation Research Program at Hunter College in collaboration with advocacy organization Open Plans. The report challenges the prevailing narrative that autonomous vehicles will seamlessly improve urban transportation.
Using data publicly shared by autonomous driving technology company Waymo, alongside local data from the New York City Taxi and Limousine Commission and the city’s Department of Transportation, the study reveals a complex reality: Robotaxis may not be markedly safer than professional human drivers and could dramatically increase vehicle miles traveled on already gridlocked streets.
Because Waymo has shared the most public data to date, the report uses the company’s operations in California and self-reported safety data as a benchmark for the broader robotaxi industry rather than to single out a specific operator.
The True Safety Comparison: Robotaxis vs. the Professional Drivers They Would Replace
Waymo benchmarks its safety data against the average human driver. However, robotaxis are poised to replace professional for-hire vehicle drivers, including Uber and Lyft drivers, as well as traditional yellow taxis. City for-hire vehicles are 14-times safer than the average human driver in New York City, which makes that the more accurate comparison. Robotaxis appear to be involved in fewer injury-causing crashes, but the data show troublingly higher severe outcomes when compared directly with New York City’s existing for-hire fleet.
The Good: Nationally, Waymo vehicles were involved in approximately 67% fewer injury-causing crashes (ranging from minor injuries to fatalities) per million miles driven — roughly one-third the rate of the city’s for-hire vehicles.
The Critical: When isolating “Killed” or “Seriously Injured” crashes, the trend reverses sharply. Waymo’s nationwide rate per million miles is one-and-a-half-times that of the city’s for-hire fleet. Furthermore, Waymo’s rate in the San Francisco Bay Area is more than three times higher than that of the city’s professional drivers.
Due to the limited miles driven by Waymos and data constraints, it is difficult to concretely and conclusively say they are more or less safe than for-hire drivers in New York City. However, these initial severe crash metrics warrant significant caution and further scrutiny.
The Congestion Multiplier: More Empty Miles on the Road
A core promise of the autonomous vehicle industry has been the reduction of urban traffic. However, the study finds that replacing human-driven Ubers and Lyfts with robotaxis could increase total vehicle miles traveled due to “deadheading” — miles driven while the car is empty and waiting for a fare.
The report highlights a sizable efficiency gap: Waymo’s miles-traveled multiplier (total miles driven to serve a single passenger mile) sits at 1.71, compared to 1.49 for New York City’s current high-volume for-hire fleet. This 14.8% efficiency gap means that a 1:1 replacement of current rideshare trips with robotaxis could lead to more vehicle traffic to move the same number of people.
The Parking Reality: Why No Parking Leads to More Traffic
A critical differentiator for New York City is its heavily constrained curb space. In California, robotaxis frequently pull over and park while waiting between rides, an estimated 58% of that wait time. In the space-constrained Big Apple, finding a spot to sit idle is nearly impossible.
The study models this friction, showing a strict mathematical reality: for every 1% decrease in parked time while waiting for a fare, a robotaxi’s overall deadheading miles increases by 1.5%. For example, if Waymo vehicles were only able to park 33% of the time while waiting for a ride in California, their deadheading miles would increase by a whopping 37%. Without a dedicated place to stop, these vehicles have no choice but to continuously move — increasing traffic significantly.
The Curb Space Crisis: Endless Circling on City Streets
Without sweeping policy interventions to reallocate precious curb space for autonomous-vehicle waiting zones, robotaxis will be forced to endlessly circle the block. This behavior would create an unprecedented gridlock multiplier, flooding Manhattan’s dense commercial corridors with empty cars that generate zero consumer value while actively exacerbating local congestion and emissions.
“While robotaxi technology is groundbreaking, the underlying reality perpetuates our current system: a focus on single-use vehicles over public transportation and active mobility,” said Sara Lind, Co-Executive Director of Open Plans. “This report shows that not only would robotaxis continue trends of increasing driving and congestion, they may very well exacerbate these issues. Cities should use this moment to update parking policies, explore fees on vehicle miles traveled, and pursue people-centered planning.”
“The robotaxi pitch rests on improving safety, but this study shows that the case is not yet settled,” said Kelly McGuinness, Director of the Sam Schwartz Transportation Research Program. “Compared to New York City’s current for-hire system, the safety claims weaken. Unregulated, the industry also brings its own adverse effects: driverless vehicles circling our streets empty, adding congestion without accountability. Cities need data and regulatory tools that match the complexity of what may be coming."
“There’s a mantra going around that autonomous vehicles are more than 90% safer than human driven cars. This report delves into the data and makes it clear, there is no solid evidence as of yet, to make such a claim compared to the for-hire vehicles already serving this city,” said Sam Schwartz, founder of the Sam Schwartz Transportation Research Program. “We find that NYC taxi and Uber/Lyft drivers may in fact be safer per mile.”
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About the Sam Schwartz Transportation Research Program at Hunter College
The Sam Schwartz Transportation Research Program at Roosevelt House at Hunter College focuses on cutting-edge urban mobility solutions, prioritizing safety, equity, and sustainability in public transit and traffic infrastructure.
About Open Plans
Open Plans is a non-profit organization dedicated to transforming how people experience New York City’s streets, using deep research, grassroots advocacy, and policy change to reduce driving, reclaim space for people, and build connected neighborhoods.
