Uber has defied regulators in California by vowing to keep testing self-driving cars on San Francisco roads, despite being told it needs a special state permit.
Earlier this week, the ride-hailing firm began testing Volvo SUVs fitted with sensors that enable the vehicles to steer, brake, and accelerate – though an actual driver is still behind the wheel.
But California’s Department of Motor Vehicles (DMV) has demanded the company obtain a test permit, while Uber says it dosen’t need one, due to the safety driver being behind the wheel.
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State prosecutors have subsequently threatened to take legal action, with the California’s attorney general ordering the company to cease the tests immediately.
As The BBC reports, just what form that legal action will take has yet to be confirmed, but is likely to be a court order for Uber to stop the self-driving service immediately and apply for the permit.

A letter from California’s Department of Justice lawyers states that if Uber doesn’t apply, “the attorney general will seek injunctive and other appropriate relief.”
Companies such as Google have obtained the permit which costs $150 (£120) for 10 vehicles, but Uber’s Anthony Levandowski, head of the firm’s self-driving programme, argues the vehicles should not be classified as ‘autonomous’.
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Levandowski says because the Volvos have actual drivers at the wheel, the cars are similar to Tesla’s vehicles, which have the Autopilot feature, allowing them to steer, accelerate, and brake autonomously but with a person in the driver’s seat.
Spokeswoman for California transport regulators, Melissa Figueroa, said the state would take action “early next week” if Uber continued to disregard the demand that it apply for a permit.
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Should Uber comply? Let us know what you think of the situation in the comments.