Well, there isn't really enough information here to say that the self driving nature is unrelated.
The self driving cars seem to be a little accident prone and could be behaving in logical but unexpected ways by breaking, changing lanes, or halting in situations where a human driver would not.
They may additionally lack contextual awareness to make gut calls about whether or not it is appropriate to stop or change lanes given the driving behavior, distance and breaking frequency of the cars behind them.
Split action response times and lots information about whats going on in front of the car is great for preventing accidents where the car is legally responsible but I can see scenarios where you could see them indirectly causing accidents which can be blamed on the other party but were partially based on the driving behavior of the car itself.