There are no federal laws requiring background checks for service workers such as TV installers or handymen, and only spotty local laws requiring service companies to do background checks. But some of those workers are actually violent felons who have even attacked customers inside their own homes.

Sally Bock's little girl was just 4 when she was chased around her own living room by a sexual predator. He was there to fix the family's fireplace, sent by a company Bock trusted. "It was a well-known company that did lots of work in homes around Seattle," Bock said, so she figured the worker they sent was safe: "I had no reason to stop and think differently."

All seemed normal: He came in wearing a uniform and started working. But while the baby sitter was in the next room, James Warning turned his attention to Sally's daughter, playing just feet away.

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"He said to her, 'Let's play a game. I want you to be as quiet as you can,'" Bock said. "He exposed himself to her and started to touch himself. He wanted her to take off her clothes, and she managed to keep the couch between herself and him so he wasn't able to touch her.

"It was terrifying," Bock said. "It's a feeling of total loss of control."

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Even more terrifying, James Warning had a criminal past as a violent felon who had spent 15 years in prison for attacking another little girl. His rap sheet includes convictions for kidnapping, attempted child molestation and attempted murder. That reputable company that sent him never did a criminal background check.

"And we let him into our living room," Bock said. "It was the most horrific thing anyone should ever go through in their lives."