Agent of Death of an Innocent

I was recently responsible for the brutal murder of a young deer. I was running late at night along a dark road, which is already scary enough if you're the kind of person who imagines battling mountain lions, slaying them, and then fending off the other mountain lions that converge on your fresh kill. Every time I hear something stir in the brush, I double my pace, hoping the pounding of my shoes and the power of my run makes me seem bigger than I really am. This time I heard the rustling directly in front of me so I slowed down, and sure enough, a dark form darted out in front of me. At first I though it was a small predator, but as soon as it stepped onto the road, I could tell it was a deer, young, sleek, and bounding across the road like a giant jackrabbit. Really, it looked like a giant hare, with legs built like springs. The headlights illuminated it so well.
I don't remember if I was standing or running, but the outcome was so certain I saw it happen before I experienced it. Car speeding down the road, deer hurtling towards it, just out of range of its lights. When they crashed, the deer flew 20 feet, on a diagonal, onto the side of the road. Clearly, there had been conservation of momentum, which was fortunate for subsequent cars. (The anterior chassis of my car was recently devastated by a giant dead deer lying in the road.) Anyhow, the deers trajectory had clearly been a product of both its own previous velocity and that of the speeding automobile, which had been generously delivered by way of collision. I paused my run and contemplated the car, which didn't seem very damaged, and, as if it were an autonomous entity (or contained a man inside it), very apparently slowed a little, considered stopping, thought better of it, and drove on as if nothing much had happened. I was too scared to cross the road to check on the deer, lest the same fate should be visited upon me (I'm not any more reflective than a deer). But I imagined checking on it, considering whether it was completely dead or flailing about like a rabid zombie eager to bite me. I thought that maybe I should put it out of its misery--but how? Jump on its head? What if my weight wasn't sufficient to crush its skull? What if someone saw me? These remain serious concerns.
I don't think I really felt much, except a little frustrated that the beast was so dumb. But one thing was surprising. The thump it made when it hit the car was fairly nondescript. Maybe it sounded a little like the time I decided to trot over the top of my car and put a dent in the roof. But otherwise nondescript.