Early in the development of autonomous and semi-autonomous vehicle suites, people started asking logistical questions. Common questions emerged like, “Can I read or text while using a self-driving function?” Well, one of the other questions people had pertained to alcohol and self-driving cars. Most notably, with the advances in technology, is it still illegal to be drunk in a car that drives itself?

Even if the vehicle can drive itself, you can’t be drunk behind the wheel of a self-driving car

Here’s a rule of thumb: if you’re going to sit behind a steering wheel, don’t drink. You shouldn’t have a blood alcohol concentration (BAC) above 0.08 in most US states in the driver’s seat, either. Most self-driving vehicle applications, namely SAE Levels 0 through 3, will require a driver to take over in one way or another. As such, you can net yourself a DUI even if the car is steering, accelerating, and braking for you.

Things get a bit murkier with automated taxi services like Waymo and Cruise. Sure, a Waymo Jaguar I-PACE will pick you up and drive you to your destination in Phoenix, Los Angeles, or San Francisco. However, many of the service’s vehicles still have controls like a steering wheel. 

Consequently, an argument could be made that a passenger is still “in control” of the self-driving car. As such, that could mean a DUI if you’re drunk. According to Waymo One’s policies, passengers cannot drink alcohol while in the vehicle. However, the policy doesn’t say anything about already-inebriated passengers.

Level 4 and 5 Robotaxis without wheels might change things

Still, not every self-driving car has a steering wheel. For instance, the incipient Tesla Robotaxi will fetch and deliver two passengers completely free of a steering wheel. Instead, the Robotaxi will travel from point A to point B devoid of a driver. So, is it still a legal no-no to enjoy drinks and jump into the cabin of a driverless car like Tesla’s Cybercab?

In the case of the Tesla Robotaxi, the answer is maybe. Tesla CEO Elon Musk wanted to launch SAE Level 5 autonomous vehicles by 2020. While that didn’t happen, the upcoming Cybercabs might meet the Level 5 requirements. To do so, the self-driving EVs would need to operate anywhere without human-operated controls like a steering wheel or gas pedal. If they do, an autonomous taxi of the like would be as much of a driver-operated car as a city light rail car.

In that case, good-timers would likely be able to treat driverless cabs like real cabs when it comes to riding with a BAC above the limit. However, when it comes to self-driving cars with steering wheels and other control surfaces, you might want to stick to a more traditional rideshare service like Uber or Lyft.