Probably a prosecutor that works for some local government that could be also be liable for letting Uber operate that car in their jurisdiction. I imagine that discussion happened.
https://www.azcentral.com/story/news/local/tempe/2019/03/19/...
The UK actually has a law against this, see "Causing Death by Careless or Inconsiderate Driving (Section 2B of the Road Traffic Act 1988, amended by the Road Safety Act 2006, s. 20)" here: http://www.brake.org.uk/news/15-facts-a-resources/facts/497-...
It means you can be prosecuted for causing a death in a moment of inattention. It's a bad law from both sides: As you can see from the link above it doesn't satisfy the charity (who want stronger penalties), while at the same time being a catch-all law which could catch anyone out who drives, even if they are generally very cautious drivers.
By the way I should add there was already a separate law for causing death by dangerous driving.
One more reason why we need self-driving cars I suppose.
Executives must be prosecuted when their money saving results in deaths or else there is no incentive for them not to make this trade off.
When I took the Uber self driving cab in Pittsburgh (randomly called on my Uber), there were two people in the car.
One person was a driver, and the other person was in the passenger seat with a laptop. They were both very polite. The person with the laptop was very focused and watched the sensors take in information.
The driver -- at least in my case -- was very cautious and almost never let the car do anything by itself. He was almost driving it the whole time.
This is right after Uber brought over the team from Carnegie Mellon (so 2015 ish?).
I would expect them to be very careful with a passenger in the car scrutinizing but much less so in a test car. If a high enough percentage of the millions of miles these companies are doing are tests without passengers, there could be a lot of road miles happening with a single overburdened driver that the public isn't seeing much of.
If you think their car isn't safe; don't buy one and don't be driven in one. It isn't reasonable to say they can't have the occasional accident though.