"As far as the sexual abuse case goes, this is a really horrible one. This girl was not only victimized. She was terrorized," Fresno County Sheriff's Office spokesperson Tony Botti said.
Ferguson was originally arrested back in April, but the District Attorney's office did not file charges at that time.
So detectives kept searching and found more evidence to move the needle forward and arrest him again earlier this month.
"A lot of it is victim testimony. What we got from this young lady really lined up with some other people that we talked to," Botti said.
The detailed complaint alleges Ferguson had recurring access to the child he assaulted for years, starting when she was younger than 14.
It states several of the assaults happened when the victim was unconscious and, at one point, even turned violent.
"And she pointed out her ear being bitten and, apparently, there's evidence of that happening," ABC30 legal analyst Tony Capozzi said.
Capozzi says Ferguson's past shows similar offenses that may point to him being a habitual sexual offender.
"[The complaint] points out that as a juvenile, he was convicted of other sexual offenses, then they got increasingly worse, increasingly serious," he said.
Sierra Unified confirmed to Action News that Ferguson worked as a bus driver during the time of the incidents.
At this point, authorities do not believe he used this position to gain access to any further victims.
"It's a scary thing for parents. You put your child on a bus and you think they're going off to school and they're gonna be safe if you come home," Capozzi says. "But if you have a bus driver that has these types of convictions is doing something in his home. Is he doing this to the young children on the bus?"
Ferguson has posted bail and is expected to be arraigned in court on August 22.
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