That is a big concern with any widespread implementation
With hundreds or thousands of self-driving vehicles, liability issues will be a drop in the bucket.
But with tens or hundreds of millions of them, that changes thing dramatically.
Today, when one citizen crashes into another, there are de facto liability limits (mainly, you can't sue someone for more than they have). But in a world with 100M self -driving cars, now every car crash is backed by a billion dollar company.
Personal injury lawyers will have a field day unless some well thought out legislation cuts that off at the pass.