The popularity of ride-hailing app Uber has proven that people are comfortable getting into a stranger's car, but would you ever accept a ride from a driverless vehicle? Uber is counting on it, but some early testing of self-driving cars in California lasted only about a week. In mid-December, the company launched its self-driving program in San Francisco ahead of getting approval from the California Department of Motor Vehicles, which revoked the test vehicles' registration mere days afterward:

Uber’s defiance of regulators was centered on its stated belief that its vehicles weren’t fully autonomous because they had a driver in the front seat who could take the controls whenever necessary. Rivals such as Alphabet Inc., Tesla Motors Inc. and General Motors Co. all have been granted the state permit.

California’s attorney general had threatened to sue Uber, but ultimately the DMV took the simple action of invalidating the registrations of 16 vehicles, giving police authority to remove the vehicles from California streets. That prompted Uber to capitulate.

While the state government requires autonomous vehicles to have appropriate testing permits to operate on public roads, Uber has indicated it's commitment to innovation in getting these cars on the road. You can read more about Uber's San Francisco self-driving car tests here.