Curiously enough Google could have access to how fast humans usually drive through that street.. if they record people's Google Maps trips, they can show the court that "Look, 80% of Google Maps users drive through here at 30 mph!".

Waymo itself has this as well. They record their drives after all which means they know the speed of the vehicles around them.

They even wrote a blog post about it:

https://waymo.com/blog/2023/07/past-the-limit-studying-how-o...

Google might even know how many drivers aren't obeying the speed limit or slow-rolling through stop signs. I wonder if they already have partnerships with law enforcement to detect areas where the traffic law is more ignored than others.