Some cars these days might be able to drive themselves, but unless you run a multibillion dollar robotaxi company, they still need a fully conscious — not to mention sober — operator behind the wheel.

That’s a lesson one San Francisco man learned the hard way, after he was caught dead asleep behind the wheel of a Tesla on Full Self-Driving (FSD) mode last week — surrounded by evidence of a binge that’d probably be cause for alarm even in the safety of his own home.

The Tesla was flagged by a “concerned” motorist who saw it driving around Vacaville city, the San Francisco Chronicle reported, in the suburbs of San Francisco.

After police officers stopped the Tesla, they found a man slumped over in the driver’s seat, decked out in a sweat suit and surrounded by a buffet of pizza and cheap wine.

“The investigation ultimately provided evidence that the driver was under the influence of both alcohol and marijuana, and he was arrested for DUI,” the Vacaville police department said in a Facebook post.

“California drivers are permitted to use newer assistive driving safety features in their vehicles,” the department continued, “but just like every other driver on the road, they still need to be conscious, alert and not under the influence while operating them.”

Having been arrested at around 11am on a Wednesday, it isn’t known how long the one man stag do was meandering around the city for. There’s also a question of how Tesla’s FSD mode allowed the driver to pass out without any objections.

Under normal circumstances, an internal camera is supposed to monitor Tesla drivers to ensure their hands are free and their eyes focused on the road. It’s technically possible to disable the alert system with a 3rd party device or even with googly eye glasses, though it isn’t known if the merry reveler was using those during his joy ride.

Either way, if there’s a lesson to be learned here, it’s that Tesla may be able to handle the driving, but a breathalyzer still requires a human touch.

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