I read an article about self-driving cars a couple months ago that from memory discussed most of the accidents or events to date with them resulted from problems in dealing with erratic drivers in other cars. They seem to get rear-ended a lot.
Google self-driving car involved in first injury accident | Fox News
I kind of have my doubts about this technology. There's no doubt it works and works fairly well but somehow I'm re-minded of the bogus Audi unintended acceleration fiasco from the mid-80s (right after we bought my wife a new Audi 5000S - year right, a 110 HP motor can overpower 4 wheel disc brakes). Audi barely survived that idiotic affair here in the US. There will be a series of accidents and injuries - probably caused by other drivers - and the personal injury lawyers will show up and the lawsuits will start claiming the cars and technology are at fault. After awhile insurance costs and public perception of the technology will take a big hit after a few accident victims show up on network news and websites (if it's on TV or the internet - it must be true) - and before long they won't be able to sell one for any amount of money and manufacturers will drop them as fast as they can. At least that's my forecast.