MOUNTAIN VIEW, Calif. (KGO) -- You may have seen those self-driving cars, primarily from Google, tooling around the Bay Area. New questions have been raised about their safety.
Pressure from a consumer group and the news media prompted Google to reveal accident numbers.
All over Silicon Valley, companies are working on self-driving or autonomous vehicles, but Google has been one of the first, starting six years ago. Until Monday, the number of accidents it has had has been under close guard.
Four states allow testing of self-driving vehicles on public streets and highways. The goal is to let technology take over the driving in a bid to improve safety and reduce injuries. Google has equipped 23 Lexus SUV's for testing.
"It is particularly incumbent upon them to be absolutely open and candid about what's working and what's not working," John Simpson from Consumer Watchdog said.
Simpson is the privacy project director at Consumer Watchdog -- a nonprofit that tried to find out how many accidents Google's self-driving cars have had, asking both Google and the DMV -- both declined.
"If the cars are safe, why wouldn't they want to disclose that to us? It certainly makes you wonder if they're not disclosing what's going on," Mountain View resident Mike Garvin.
Late on Monday, Google released the numbers covering six years and 1.7 million miles.
There have been 11 minor accidents with light damage and no injuries. Its vehicles have been hit seven times from behind and sideswiped twice. One vehicle was hit by a car rolling through a stop sign. Google reports, "Not once was the self-driving car the cause of the accident."
James Sweeney, Ph.D., a professor of management science and engineering at Stanford, says such numbers can be misinterpreted during the testing and development stage.
"I don't see a good reason for reporting all of the failures of the evolving technology, but we will want a complete reporting of the technologies that become public so people can make a judgment," Sweeney said.
Another company, Delphi, took a self-driving car cross-country from San Francisco to New York without incident. Last year, however, one of its cars was hit when another vehicle struck it crossing the median.
Google admits self-driving cars involved in 11 minor accidents