But buried on its website is a disclaimer that the $8,000 system doesn't make the vehicles autonomous and drivers still have to supervise it. The Society of Automotive Engineers, or SAE, has developed five levels to describe the functions of autonomous vehicles. Tesla is among 60 companies with permits to operate autonomous vehicles with human backup drivers in California, the No. Before Tesla is able to put fully self-driving vehicles on California roads, it will have to get another permit from state regulators. At the same time, he says that testing the system with vehicle drivers could be beneficial and speed adoption of autonomous vehicles.