I hope somebody saw the mugging. Too bad he didn't have the means to do harm to the mugger at the time of the incident. That being said, I doubt this will go well for Mr. Martinez as, apparently, at the time Mr. Martinez ran over the mugger he was no longer a threat.
Still, he had no reason to stick around to see if the guy was dead or incapacitated. This really wasn't like a "hit and run" ~ after all, it wasn't an accident. (ROTFLMAO).
Had he killed the mugger while the mugger was holding the gun on him he would still face murder charges in Conn. It's the blue state way.