On Wednesday, Uber expanded its driverless test fleet to the streets of San Francisco, offering ride-hailers a chance to drive in one of “a handful” of Volvo luxury SUVs. The news came months after the ride-sharing giant unveiled a driverless Ford Focus test fleet in Pittsburgh–the first of these vehicles available to the public in America.

The move elicited a quick response from regulators: Less than 24 hours later, the California Department of Motor Vehicles issued a statement demanding Uber to take the vehicles off the road, calling the move “illegal.”

Like Singapore’s driverless taxis and Uber’s Pittsburgh fleet, the San Francisco vehicles had a testing driver as well as a trained engineer in the passenger seat–in other words, the fleet was not entirely “driverless.”

Jeffrey Miller, IEEE member and associate professor of engineering at the University of Southern California sees San Francisco as an obvious spot for Uber’s driverless testing, since it’s a tech hub. Also, “Uber does have an office there, so keeping the testing of these vehicles close to their offices is a smart move.”

But unlike the previous experiments, Uber did not have permission from California to have these vehicles on the road. State law requires a permit for these types of autonomous vehicles–currently, 20 companies have it–which Uber lacks. The ride-sharing giant argued that, since its vehicles were being monitored by test drivers, the requirement didn’t apply.

Top autonomous driving experts questioned Uber’s strategy with the fleet.

“I wonder how this particular step fits into Uber’s long game,” said Bryant Walker Smith, associate professor at the University of South Carolina and an expert in the legal implications of autonomous driving.

Smith raised concern with the definitions around driverless vehicles years ago, which, he said is “at odds with the goal of the regime–to build trust in the systems and developers.”

SEE: Our autonomous future: How driverless cars will be the first robots we learn to trust (TechRepublic)

“If I were advising Uber, I’d ask what their end game is and how this legal argument advances that end game,” said Smith. “It’s plausible textually, but nonetheless, in tension with the regulatory regime. This regime was, in part, about building trust,” he said.

Uber taking a risk here wasn’t entirely unexpected.

“Uber and its self-driving car leadership have a history of pushing the boundaries, not wanting to wait for permission because it slows down innovation,” said Michael Ramsey, autonomous vehicle expert at Gartner. “In this case, Uber will take a small set back until it gets its license. However, you have to wonder why Uber doesn’t simply move its test somewhere else. There are plenty of cities that would be happy to host this technology without regulatory entanglement.”

Smith echoed the point. “We’ve seen this play out before–when UberX launched in various cities,” he said.

Beyond the regulatory and practical issues, this move seems to highlight that Uber wants to be seen as a “key player in driverless vehicles,” said Miller. “Uber is making a push for convincing the world that they are going to be a large player in the driverless vehicle market.”

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