You know what's funny? When I first heard about automated cars, I always figured it'd be easier to disrupt them physically than it would be digitally. Of course, I never figured how to do it, but you came up with a good example right there.The funny thing is if you want to get an autonomous car to slow down abruptly, run in front of it. You need not worry one iota about its reaction time. Hijacking an autonomous vehicle would be as simple as having a bunch of dudes swarm it so it couldn't get anywhere and then bust the window and grab the occupant. No LIDAR necessary - do it Somalia-style.
Autonomous vehicles leverage routine. The examples you list above are all about improvisation. There's the additional issue of the legality of any enforcement or interdiction performed by a non-human agent; the simple example of red light cameras should point out how sticky that's gonna be. Cop cars, ambulances, fire engines and tanks are gonna have drivers for a long, long time to come, I reckon.