Even autonomous vehicles aren't immune from traffic stops.
In a blog post, the police department said the officer noticed cars stacking up on a major thoroughfare behind a slow-moving vehicle that was traveling at 24 mph in a 35-mph zone. He cut around and pulled up alongside the vehicle, then realized it was a Google self-driving car. Police said the car's passenger took over the controls and pulled the vehicle over.
"The officer stopped the car and made contact with the operators to learn more about how the car was choosing speeds along certain roadways and to educate the operators about impeding traffic," the department said.
In a separate blog post, Google said the prototype vehicle's speed is capped at 25 mph for safety reasons.
"We want them to feel friendly and approachable, rather than zooming scarily through neighborhood streets," the company said.
The company said their vehicles have driven 1.2 million miles without being ticketed.
Sgt. Saul Jaeger of the Mountain View Police Department said officers regularly see self-driving cars on road, but this was the first time they pulled one over.
"Our job is focused on safety and enforcement of the law," Jaeger said. "In a case like this, we're unbiased if it's an autonomous vehicle, or a Bentley or a bicycle."
Google is just one of several companies that are working on self-driving car prototypes. Automakers such as Delphi and Tesla also have developed driverless vehicles.
The market for these cars could be substantial. According to a January study by industry research firm IHS Automotive, as many as 250,000 self-driving cars could be sold each year globally by 2025.
But motor vehicle laws have yet to catch up to the technology. Current regulations in many states do not have provisions for self-driving cars. In New York, for example, drivers are required to keep one hand on the steering wheel, according to a 2014 law review article by Bryant Walker Smith, an affiliate scholar at the Center for Internet and Society at Stanford Law School.
And it's not clear who would be responsible for traffic violations. On the Mountain View police blog, the department said the human in the car would receive the ticket. But California is still working on laws for a situation in which there is no driver. All of the Google cars, at this point, have humans on board.
Times staff writer Joseph Serna contributed to this report.
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