Two groups, The Center for Auto Safety and Consumer Watchdog, have called on the US Federal Trade Commission (FTC) to investigate the Tesla Autopilot system.
The two organisations claim Tesla and its CEO, Elon Musk, have deliberately misled and deceived "consumers into believing that Autopilot is safer and more capable than it is known to be", and have "made it reasonable for Tesla owners to believe, and act on that belief, that a Tesla with Autopilot is an autonomous vehicle capable of 'self-driving'".
According to the advocacy groups, Tesla owners and those interested in its products are likely to be deceived by its boast of having "Full Self- Driving Hardware on All Cars", claims it reduces the likelihood of accidents by 40 per cent, and videos of Tesla vehicles autonomously driving on busy streets.
They also criticise Musk's pronouncement "the probability of an accident with Autopilot is just less", and relating Tesla's Autopilot with autopilot systems used by commercial aircraft.
In their letter to Joseph Simons, the FTC chairman, they assert Musk has even acknowledged "Tesla consumers often perceive Autopilot to be safer than it actually is".
Tesla's Autopilot is a Level Two self-driving system, with features like lane-keeping assistance and active distance control, all still requiring drivers to stay alert and have their hands on the wheel.
More advanced Level Three systems, such as the one coming to some overseas variants of the Audi A8, allow for hands-off driving in some freeway situations.