FRESNO, Calif. -- Video from a teenager's bedroom may be the key to a sex abuse case against a former Fresno County Sheriff's Deputy.
A Fresno teenager came to her dad in 2015 with one of the worst things a father can hear from his daughter.
"She told me, she goes 'Dad, Papa's been touching me,'" the father testified.
We are not showing his face to avoid identifying the alleged victim, but "Papa" was his stepfather, Rex Garcia, who had recently retired from the Fresno County Sheriff's Office.
The girl says she woke up with two layers of clothes removed, and Garcia just left the room when she caught him in the act.
The father says he did not think anyone would believe the girl's story, so he bought a wireless video camera and set it up in her room. The first night it was there, Garcia came back to the room and lifted her blanket.
"He came in and he sat on the edge of the bed and then got up and walked out," the father said.
We are not showing the full video, but prosecutors say it amounts to sexual abuse. And they say Garcia did something similar on a couple more nights before the father delivered his evidence to police.
Officers arrested Garcia a little while later.
His defense attorney denies the video shows anything more than a vigilant grandfather figure checking on a girl in her sleep.
"Look at those videos," Antonio Alvarez said. "Doesn't show anything nefarious. Nothing at all."
Alvarez also says the girl has an issue with lying.
But prosecutors say the video backs her up, and the girl reported inappropriate touching by Garcia dating back years, even during his time as a sheriff's deputy.
"A former law enforcement officer for the Fresno sheriff's department and the Fresno Police Department betrayed this family by molesting name redacted," said prosecutor Amy Freeman.
Garcia faces up to 16 years in prison if he is convicted.
The trial should last about a week.
Dad sets up hidden camera after teen accuses step-grandfather of touching