The traffic stop was captured and posted on Facebook, where it was later picked up by Fusion, and then tweeted by the David E. Weekly, head of Google’s Rapid Rollout Lab. The rest is Internet history.

Google (GOOG) later weighed in on the incident (yes, it’s now an incident) with a post on Google+ that suggests the vehicle was pulled over because it was too slow and due to the officer’s curiosity. Here’s what Google posted Thursday afternoon:

Driving too slowly? Bet humans don’t get pulled over for that too often.

We’ve capped the speed of our prototype vehicles at 25 mph for safety reasons. We want them to feel friendly and approachable, rather than zooming scarily through neighborhood streets.

Like this officer, people sometimes flag us down when they want to know more about our project. After 1.2 million miles of autonomous driving (that’s the human equivalent of 90 years of driving experience), we’re proud to say we’ve never been ticketed!

The Mountain View Police Department (MVPD) added a more detailed account on its own blog, explaining that the officer noticed traffic backing up behind a slow-moving car (that would be the Google car) traveling at 24 miles per hour in a 35-mph zone. The officer approached the vehicle, realized it was a Google self-driving car, and stopped it to speak with the operators and “learn more about how the car was choosing speeds along certain roadways and to educate the operators about impeding traffic” per the California Vehicle Code. MVPD says it was lawful for the car to be traveling at that speed. In other words, Google wasn’t ticketed.

Much to the chagrin of every other driver behind the Google prototype, the vehicle is designed to be slow, mindful, and ultrasafe. The company is even teaching its cars how to act around kids.

As I described in my own test in September, the ride itself was so safe and steady that it was almost boring. The vehicle doesn’t have pedals or a steering wheel, only sensors and software. Google hopes to commercialize its technology by 2020. These self-driving cars have never hit another vehicle or pedestrian, according to Google. But if they did, there are a few extra safety measures built into the vehicle like a flexible windshield and a front end made of a foam-like material.

One question the National Highway Traffic Safety Administration and California’s state government is trying to determine is who receives a ticket if a self-driving car commits a traffic violation. Certainly not the passenger, right? But what about the person who developed the software or perhaps the manufacturer of the car? California and NHTSA are working on regulations to provide clarity on the matter. In the meantime, Google has said the company will take responsibility.

NHTSA is conducting a four-year study to develop self-driving car recommendations for state laws, according to information posted on California Motor Vehicle Division website. The federal agency has also issued a set of guidelines for states to consider when dealing with autonomous cars, such as requiring that the people who work the cars have special licenses.

For more on Google’s self-driving cars, check out the following Fortune video:

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