CAYLEE'S MOM DONE IN BY HER OWN LOVER

A rookie cop – who became Casey Anthony’s lover – broke the sensational murder case wide open, The ENQUIRER has learned.

Deputy Anthony Rusciano of the Orange County Sheriff ’s Department provided crucial evidence that helped police nab the Florida mom and charge her with the heartless murder of her daughter Caylee.

From text messages, e-mails and pillow talk, Deputy Rusciano learned that 22-year-old Casey was growing increasingly frustrated as a single mom. She allegedly viewed Caylee as an anchor around her neck – preventing her from enjoying the partying life.

Rusciano stunned detectives when he revealed he’d dated Casey and that she derisively referred to Caylee as “the little snot head.”

“Rusciano definitely helped detectives build a murder case against Casey,” former Secret Service agent Art Wood, who’s independently investigating the case, told The ENQUIRER.

“His information alerted police to her dark side.” Casey had reported 2-year-old Caylee missing July 15 – a month after the child vanished. As detectives in Orlando began their investigation, they received stunning information that one of their own, 24-year-old Deputy Rusciano, had romanced their prime suspect.

The officer – who joined the force only this past February – admits he was “scared” at first and told detectives he’d met Casey only once at a party.

Casey’s computer, however, revealed that Rusciano and Casey had shared many instant messages and e-mails, some of them X-rated.

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