On the day it rolled out its self-driving car fleet in its hometown of San Francisco, ride-hailing company Uber was threatened will legal action from the California Department of Motor Vehicles (DMV).
"If Uber does not confirm immediately that it will stop its launch and seek a testing permit, DMV will initiate legal action," the DMV said in a letter on Wednesday.
Uber responded, however, saying they knew about the permit, but argued that its cars do not meet the state's definition of an "autonomous vehicle" because they require a person behind the wheel to monitor and intervene if necessary.
California defines autonomous vehicles as cars that have the "capability" to drive "without the active physical control or monitoring of a natural person."
The DMV has so far issued permits to 20 companies for tests of autonomous vehicles on public roads, mostly a collection of traditional automakers and tech companies - but not Uber.
Necessary human monitoring
Wednesday's launch in San Francisco marked an expansion in Uber's deployment of self-driving cars, which it first launched in Pittsburgh in September. The trial allows everyday people to experience the cars while Uber works to identify glitches before expanding the technology's use elsewhere.
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Uber is testing self-driving cars
Uber's self-driving tests in San Francisco will begin with a "handful" of Volvo luxury SUVs which have been equipped with sensors, enabling the cars to steer, accelerate brake, and even decide to change lanes.
Uber believes its technology is ready to handle all this safely, though according to Anthony Levandowski, the leader of Uber's self-driving program, Uber's cars simply aren't advanced enough to drive themselves without human monitoring. "We're just not capable of doing that yet," he said.
"Therefore, the Volvos are not autonomous and do not require a permit," Levandowski added.
Operating without a permit arguably gives Uber a competitive advantage. Companies with one must report to the state all crashes and every instance in which a person takes control during testing.
All that information is public. To receive a permit, a company must show proof of insurance, pay a $150 fee and agree that a human driver can take control of the vehicle.
Uber runs red light
Once the pilot scheme comes to an end, the Uber's ultimate vision is to sell technology to the public which supporters argue will save thousands of lives because it doesn't drink, text, fall asleep or take dangerous risks.
Adding to Uber's woes on Wednesday, local media aired a video of a self-driving Uber running a red light, which was captured by a bystander.
Uber said the incident was caused by human error - suggesting that the car was not in autonomous mode - and was not carrying passengers. The driver has reportedly been suspended.
