I agree with ya'll on the opinion that the driver may have not even noticed he hit something, or just thought it was a deer. Two guys I went to highschool with were drunk driving down the freeway, at night, on their crotch-rockets racing each other. One of them lost control and both of them went down. The bikes and both of them were off the freeway. One of the guys died in the accident, but the other one was still alive, hurt obviously. His head was still on the road and a driver not noticing something was in the way, ran him over. The driver just thought he hit a coyote and didn't stop (in New Mexico). Later the driver was watching the news and seen the accident and realized he was driving that same stretch of freeway at about the same time. Called the authorities and sure enough, he hit the one guy that was still alive. Driver wasn't charged with anything... So yeah, just showing that it can happen to anyone.