LANCASTER (CBSDFW.COM) – Maria Escamilla says she was brutally beaten, stabbed and sexually assaulted more than year ago by her ex-boyfriend.

Jose Arreola was arrested for the attack and is now awaiting trial. He wears an ankle monitor as a condition of his bond.

It’s supposed to track his every move.

“It puts my entire family on edge,” says Maria Escamilla. “Constant worrying!”

Last week, the monitor went dark for more than six hours.

At a hearing in Dallas County Monday the District Attorney’s office argued he cut it off himself.

His attorney, Michael Todd, told Dallas County Judge Fred Tinsley that it came off accidentally while Arreola was jumping on a trampoline.

“These ankle monitors are very hard to get off,” said Ron Stretcher, the Dallas County Criminal Justice Director. “Almost all the tampering violations we get either come because the monitor has been cut. The monitor has gotten wet. Or they have tampered with the base unit.”

According to the Dallas County Department of Justice, since September of 2009 56 out of 847 clients with ankle monitors either tampered with their device or had some sort of other violation.

The department says the client is responsible for paying for the ankle monitor, which can run between $7 to $10.

“The cost of a jail bed for the day is $53.13,” says Stretcher. “These devices have saved the county more than $125,000 in jail bed expenses.”

CBS 11 news wanted to talk to Arreola about what happened with his ankle monitor, but after his hearing on Monday morning he ran away from our camera outside the courthouse.

Judge Tinsley who didn’t think Arreola tampered with his ankle monitor has turned down all requests for comment. So has Arreola’s attorney.