I agree with mumboking. If you go into a corner to tight, or even turn, they might slam themselves into a tree.
I agree that there should be a scenario that you run away from the police. I also see that the AI isn't good enough yet and that this would require a mod.
newest game update 0.5.6? well we got "chase" and flee AI functionality back, its' not the best but you can play cops and crims now )
I think if the developers could somehow make it to where the AI can use the AI control thing where they can follow the road to help them better chase you