WASHINGTON -- Self-driving cars are not ready for prime time, the National Highway Traffic Safety Administration said last week as it urged states to require motorists to have special licenses and be in the driver's seat at all times to operate the vehicles.
Top officials are trying to strike a balance, knowing that driving could become safer with the technology that several car companies and technology giant Google Inc. are developing. But the regulators are not yet convinced the vehicles are safe.
Early safety problems could keep the technology from being accepted, NHTSA Deputy Administrator David Friedman said in an interview.
"The last thing we need, the last thing the public needs, the last thing the industry needs, is a bad actor to get out ahead of the technology," said Friedman, whose predecessor, Ron Medford, left last year to run Google's self-driving cars project. "We're going to try to make sure that doesn't happen."
California, Nevada and Florida have passed laws allowing Google, as well as car companies such as Toyota Motor Corp. and Audi AG, to test self-driving cars on public roads. Other states are thinking of following suit.
In addition to states requiring special licenses and for the licensees to be in the driver's seat at all times, NHTSA's policy released last week says that the operators should be able to quickly take control of the vehicles if needed and should report any malfunction, crash or near miss to authorities.
NHTSA also said it will launch a four-year research project into the safety of automated features, including fully self-driving cars.
The agency may need to decide what to do about the vehicles within a few years. Engineers working on Google's project have suggested that self-driving cars could be ready for the market as soon as five years.
"We look at this technology as having the potential to really expand commercially over the next 10 to 20 years," Friedman said. But "if Google really steps on the accelerator pedal, we're going to do the same. We're going to be ready."
Google did not return a message seeking comment.
Car companies mostly plan to ease into automated driving. Rather than introducing self-driving cars, they are adding features such as adaptive cruise control, automatic braking and lane-keeping assist technology to get drivers -- and their engineers -- used to the technology.
Fairly soon, "you'll see pieces of autonomous driving starting to become available," Audi spokesman Brad Stertz said. "That doesn't mean you're going to be able to kick back and not be involved in the act of driving at all."