Investigators will likely confirm or deny this, but based on the poor weather, I wouldn’t be surprised to find that the car was being human-driven. Of course, Waymo does do testing under inclement weather, which makes sense as automated vehicles will need to drive in all kinds of conditions, though their safety report does specify “behavioral competencies” of their safety drivers that includes

43 Detect and Respond to Unanticipated Weather or Lighting Conditions Outside of Vehicle’s Capability (e.g. rainstorm)
44 Detect and Respond to Unanticipated Lighting Conditions (e.g. power outages)


...both of which, weather and lighting conditions, appear to be factors in the conditions of this incident, and likely would have prompted a safety driver to take control.

Of course, humans make mistakes while driving, which is part of why anyone is bothering trying to figure out how to make machines do it at all, and these conditions could be challenging for people as well.


Waymo issued a generic-sounding statement saying:

“The trust and safety of the communities in which we drive
are paramount to us, and we will continue investigating this
incident in partnership with local authorities,”


...and they do seem to have contacted California’s DMV, and will file a crash report for evaluation.