In February, his SUV veered off a California highway and down a steep embankment. Fox was ejected from the vehicle and found 600 feet over the side.
The CHP says there is no evidence of any kind that indicates the crash may have been a suicide.
The 62-year-old East Cary Middle School teaching assistant was charged in January with indecent liberties with a minor.
Fox had worked at the middle school since the fall of 2009. According to the school's website, he was an in-school suspension teacher.
Police had said the victim did not attend East Cary Middle, but warrants reveal the inappropriate touching happened when the child was placed in a teacher assistant-student relationship with Fox. They said the crimes took place over the course of several months in a residential setting and that one of the child's parents notified authorities.