Tesla Drivers Test Autopilot's Limits, Attracting Audiences---and Safety Concerns

Tesla Inc. Chief Executive Elon Musk for years has been championing his vehicles' driver-assistance system called Autopilot and forecasting that self-driving cars are an emerging reality. Some would-be social media stars and Tesla owners can't seem to wait. Param Sharma, 25, has posted multiple videos to Instagram in which he appears to operate a Tesla while in the back seat with nobody at the wheel. Police in California arrested Mr. Sharma on May 10 for alleged reckless driving after an officer said he saw him operating a Tesla Model 3 from the back seat on a Bay Area highway. Similar videos abound on social media, even though Tesla's technology is intended only as a way to assist drivers, who are instructed to keep their hands on the wheel.