DETROIT -- In a policy statement released Thursday, America's
top auto-safety agency embraced self-driving technology but
called for states to make sure there is still a person behind
the wheel while such innovations are in testing.  The National
Highway Traffic Safety Administration issued a 14-page
preliminary policy statement on automated vehicles to address
the issues arising from technology already developed that makes
it possible for the car to do the accelerating, steering and
braking.  Much of the technology already exists in modern cars.
With such "driver assistance" features, sensors in a car can
detect other cars, lanes and pedestrians. If the driver fails to
react, the technology can take control of the car and make the
necessary evasive action to avoid a collision.  Transportation
Secretary Ray LaHood has been a proponent of the new safety
technology, which he considers less prone to mistakes than a
driver. But as states permit the testing of autonomous vehicles,
the safety agency wants to err on