The case against a cab driver accused of sexually assaulting a mentally disabled passenger is moving forward.

Charges of aggravated sexual battery and sexual penetration by force were certified to a grand jury Tuesday against Ted Nelson Smith.

Witness testimony in court reveals Smith was one of Yellow Cab drivers hired by the victim's family to take the victim to and from an adult day care. The alleged incident happened in late August during a ride home.

Smith had been driving the victim for a year before the alleged incident. The family's counselor, Connie Richardson, says sexual assault often happens between the victim and someone they know.

"Being able to convince the victim that it's their secret, that there's nothing wrong with what's happening. So generally, it's about creating trust," says Richardson.

The alleged victim is a 34-year-old woman who suffers from Down Syndrome.

Smith's attorney spoke Tuesday and said the woman started and encouraged the encounter.

Smith remains in the Rockingham County Jail. His last day at Yellow Cab was August 29, the same day the woman's mother filed a complaint.