Attacks on driverless cars is going to be a big issue in the very near future. For example I can see throwing snowballs at driverless cars becoming a big thing in the Northeast by bored or mischievous kids. Growing up we used to throw snowballs at buses because we knew the driver was prohibited from stopping (plus buses were a BIG target). Driverless cars will be similarly targeted.
I can also see scam artists waiting in crosswalks till the last moment to try and purposely get hit by driverless cars in the hopes of a big payday. Lots of ways to mess with driverless cars will be invented with very little sympathy for the autonomous victims.
And have we stopped saying autonomous vehicles and are now referring to driverless cars? How about "sedan drones"?