It's a more generalised problem than you probably think, and is a factor in virtually every multi-party accident. Even if the root cause of the accident is some

It's a more generalised problem than you probably think, and is a factor in virtually every multi-party accident. Even if the root cause of the accident is someone else's human error, this still leaves surrounding vehicles with a choice about how to respond to it: whether to take damage or inflict damage, and if the latter, then inflict damage upon whom. For an AV, that's a trolley problem. For a human, it's not. We don't rationalise about such things: it occurs in an eyeblink, and gets covered under "shit happens". We convince ourselves that the outcome is inevitable, just a function of physics. But it isn't. Unlike humans AVs will have the ability and obligation to make choices in such situations; this is critical for their harm-reduction capabilities. When all of those choices are to some degree bad (which is very, very often), then it's a trolley problem. Which is why people who work on AVs are legitimately concerned with them.