Uber attributes the move to 'human error' while California licensing authority calls halt to trial, threatening legal action...

A trial run of Uber self-driving taxis has been shelved in California after one of the vehicles was filmed running a red light on the first day of the test program.

In a move Uber attributed to ‘human error’, the self-driving Volvo, one of a fleet rolled out across the city on Wednesday morning, was filmed heading straight through a red light in San Francisco around four seconds after the light went red, and as a pedestrian had begun to cross the road.

The company has been threatened with legal action unless it stops testing the vehicles on California’s streets, but Uber argues that its vehicles still have a person in the vehicle monitoring them, so the same licensing rules should apply to cars without someone at the wheel.

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In a statement to the Huffington Post, Uber said the incident was a human mistake, rather than a technical one. “This incident was due to human error,” the spokesperson said. “This is why we believe so much in making the roads safer by building self-driving Ubers. This vehicle was ... not carrying customers. The driver involved has been suspended while we continue to investigate.”

In a letter to Uber, California’s Department of Motor Vehicles ordered the company to stop testing until it had obtained a permit for operating the vehicles, threatening legal action.

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The letter read: “It is illegal for the company to operate its self-driving vehicles on public roads until it receives on autonomous vehicle testing permit.”

“If Uber does not confirm immediately that it will stop its launch and seek a testing permit, DMV will initiate legal action.”

Uber’s Anthony Levandowski contested the notion the self-driving cars need a special permit to operate on roads. He wrote in a blog post: “The rules apply to cars that can drive without someone controlling or monitoring them. For us, it’s still early days and our cars are not yet ready to drive without a person monitoring them.

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 “But there is a more fundamental point—how and when companies should be able to engineer and operate self-driving technology. We have seen different approaches to this question. Most states see the potential benefits, especially when it comes to road safety. And several cities and states have recognized that complex rules and requirements could have the unintended consequence of slowing innovation.

“Pittsburgh, Arizona, Nevada and Florida in particular have been leaders in this way, and by doing so have made clear that they are pro technology. Our hope is that California, our home state and a leader in much of the world’s dynamism, will take a similar view.”