Sounds like a situation that could have happened even if it were driven by a normal driver?
The woman just stepped out into the road suddenly, so not only was she at fault for not watching traffic, but also she broke the law in America (jay-walking).
It's sad that she was killed, but something tells me that this happens more often than we think, not just in the U.S. but all over the world... the only difference this time is that we're being led to believe that this was caused by an autonomous vehicle, and that these driverless cars aren't as safe as we think.
I've only heard of 2 incidents so far with autonomous cars, one was when a normal driver ran a red light and T-boned a driverless car at a cross junction, and the other is now with a woman stepping out into the road without any regards to oncoming traffic. So my deduction is that this proves the real threat on the roads is us, not driverless cars.