HOUSTON, Texas (KTRK) -- When LaToshia Simpson is behind the wheel of her Cadillac, she's in charge of her destination, but she recently learned someone else was aware of every mile those tires took.
"It's an uneasy feeling," LaToshia admitted to ABC13. "It's like a violation."
Derek Ester, her husband of nearly two years, is charged with unlawful installation of a tracking device- a misdemeanor.
He was arrested after LaToshia discovered an Optimus 2.0 GPS tracking device attached to her vehicle. She says the couple initially purchased the equipment to track a slingshot they rented to customers as recently as last year.
"Just in case the person didn't bring it back, we knew exactly where to go and get it," LaToshia said. "So that was the purpose of purchasing the tracker. "You can go pretty much anywhere on the web and purchase a tracker. It's just that simple."
But a device she says was originally intended for her protection was used to violate her privacy. The Harris County District Attorney's Office tells ABC13 they are seeing a spike in cases like these being filed.
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"You go to this extent to know where I'm at," she questioned. "C'mon. Just because I don't answer the phone when you want me to answer the phone? That's not necessary. Now I feel like I have to look over my back or check my car just to go to the store."
Still shaken, especially from the physical violence she says occurred when she confronted Derek after discovering the tracker, Simpson said she is grateful it didn't escalate more. She shares this warning with others.
"Pay attention," Simpson said. "Listen to what the person is saying because sooner or later, they're going to tell you what they're doing and what their intentions are.
"And if the situation is getting too violent or heated, get out. Leave. Don't worry about the material stuff. That can be replaced. But your life - you only have one. Just pay attention," she said.
Simpson tells ABC13 she's started the process of separating from her husband and plans to file a restraining order.
Her husband, Derek, is due in court next week.