A Grant Park police lieutenant let his brother's daughter move in with him so he could "straighten out" the teen, then proceeded to have sex with her on a "daily basis" when she wasn't cooking his meals, doing his laundry, or shopping for lingerie and shoes, a Will County prosecutor said.

Stephen Nardi, 45, started having sex with his 15-year-old niece within three weeks of her moving in with him in June 2010, said Assistant State's Attorney Peter Wilkes. Nardi, who was arrested by agents from the Illinois State Police and fired from his job with the Grant Park Police Department Tuesday, appeared in bond court Wednesday afternoon.

Wilkes told how Nardi offered to "help" his brother's daughter by letting her move into his Steger home, and by helping, he apparently meant having sex with her for the next year and a half. "In essence, she became (Nardi's) wife," Wilkes said, doing his cooking, cleaning and laundry.

Nardi also took his niece out shopping for lingerie and shoes, Wilkes said, and threatened to kill her if she blabbed about how he was having sex with her. Nardi, who forbade his niece to have friends of her own, went so far as to once grab the girl by her arm and fire a gun in the air as he told her to "keep her mouth shut," Wilkes said. The teen finally revealed her situation after a failed suicide attempt, Wilkes said.

Nardi faces charges of criminal sexual assault and having sexual relations within his own family. Wilkes told Will County Judge Roger Rickmon that he expects even more felony sex charges to be filed against Nardi and asked the judge to set bond at $250,000.

Nardi's attorney, Eugene Fimbianti, pointed out Nardi has no criminal history and a spotless record as a police officer for not only Grant Park, but also Steger and Kankakee. Nardi also suffers from post-traumatic stress disorder, Fimbianti said, telling how he was stricken with it after his partner was shot and killed in Kankakee.