Someone struck him with a car and killed him. I think leaving the scene after killing someone with a vehicle should satisfy any any standard of negligence.
Let me paint you a picture - an accurate picture, as agreed by both parties in a court of law. Whilst I did not witness the incident, I was an EMS responder. And whilst this did not end in a death, there are many a parallel.
A young man, in a hurry, changes his plans, and driving. He pulls in to an old fire station, turned scout hall, where some boy scouts are having a meeting. In the courtyard that was the engine apron, he yanks the steering wheel and makes his wheels squeal, sprays a little gravel.
Two parents who are outside waiting for their children yell at him. He gives them the finger. They say he's a dangerous driver and that they're calling the cops, and he'd better stay. He says "No, I'm leaving". Voices are raised.
The driver decides no, he really is leaving. The parents decide (rightly or wrongly) that he isn't - they're making a citizen's arrest. He puts his car in gear. From each side, at the same time, the parents open his car door.
They admit that it's to stop him.
He admits he panics. He puts the car in reverse and hits the accelerator - the open doors catch both parents and knock them down. The older parent breaks his hip.
The younger one, however - much worse. His head is caught between the asphalt and the bottom of the car door, and as he reverses, the man's head is dribbled almost like a basketball between the two, before the driver gets free, and flees the scene.
The other parents call the police (and EMS). The driver is picked up nearby and charged with vehicular assault and leaving the scene.
Had he, however, left the scene and immediately called 911, the parents would have been the ones charged, with kidnapping / false imprisonment. The driver's defense, and one which stood in court a great deal, was that the parents had already demonstrated a willingness to physically restrain him against his will for a tenuous "crime", and after his panic, who is to say that he wouldn't be in further physical danger?
The younger driver, as it happens, recovered fully - after an intracranial hemorrhage, surgery, a medically-induced coma, and a 1 1/2" hole placed in his skull to drain blood.
So, no - be careful to paint such broad black and white brush strokes.
Sorry, I don't see how this is relevant. Kemp struck Seth with his car, killing him, and ran away. That is a black and white issue, he hit someone minding their own business and ran without taking responsibility, turning his accident into a crime.
The situation you describe is about an altercation between parties that results in injury. It's so different from a hit and run that I'm not even sure where the logical connection is (besides both stories involving a car).
That it can't be assumed to be a fait accompli that "negligence" or vehicular homicide is involved in the scenario of anyone leaving the scene of an accident.
This isn't about what should/shouldn't be, I'm talking about how the legal system views these things. Vehicular homicide has a requirement of negligence, because traditionally the justice system sees a qualitative difference between a grandpa who backs over a grandchild who runs behind the SUV and someone who chooses to drive despite being blind drunk.
In terms of the hit-and-run == negligence...the two things correlate...a drunk driver may be so drunk that they don't realize they've killed someone. Or more maliciously, they do realize it but don't want to take a breathalyzer at the scene of the crime. However, there are cases (which does not seem to apply to the case in question) in which otherwise well-behaved drivers have killed someone unknowingly or for some reason panicked and left. It's still a crime, but it's not "homicide"
Honestly, leaving the scene should instantly turn any accident into a crime. I'm sorry that you panicked, but you need to pull over and take responsibility.
I understand that accidents happen, but choosing to leave someone bleeding on the side of the road is not an accident.