The fact that the person failed to take responsibility does not change the fact that it was an accident.
Okay, let me make a correction: the beginning
of the incident may have been an accident (although you could argue some on how much role decision paid in enabling said accident), but what the person opts to do after
the fact is less so.
You generally don't "accidentally" drive home and wash your bloody car after realizing you ran over a person. Yelling at a dying person's wife for half a dozen minutes and not doing anything to help them is hardly an "accident" anymore, either. It is no longer a split-second misjudgement, unawareness of the full picture, or inability to stop the inevitable, as "accident" would usually imply.