The grand-jury report, released at a news conference, describes the victim as a 51-year-old, 5-foot-1 woman who worked part time as a paralegal at Kerns' North Wales firm. It chronicles the events of that night in explicit detail, characterizing Kerns as having used "brute force" during the alleged attacks, which reportedly occurred after the party, both in his car and in her home.
Prosecutors said the woman went to police six days later, when physical injuries still were visible on her body.
"I give great credit to the victim in this case," said Ferman. "She was extremely courageous in coming forward and sharing what happened to her, and I think that she should be commended."
The grand jury's report describes Kerns' actions as "manipulative and predatory."
Defense attorney Brian McMonagle said his client vehemently denies the allegations.
"Anyone who knows Bob Kerns knows that he's incapable of committing such crimes, and we look forward to successfully defending this case and restoring his good name," said McMonagle.
According to the grand-jury report, Kerns offered the woman a ride to King of Prussia after a law-firm party at the Radice Restaurant, on Route 202 in Blue Bell, where employees were celebrating the recent passing of the Pennsylvania Bar Exam by one of their newest lawyers.
The victim told police she had 1 1/2 glasses of wine and a couple of shots of Limoncello at the event. Afterward, Kerns reportedly bought a $68 screw-top bottle of chardonnay from the restaurant and was handed two wine glasses. That's when he allegedly dissolved the sleep drug Ambien into the bottle and encouraged the victim to drink from it when they got into his car.
While driving her home, the woman told police, Kerns asked how she liked working at the law firm. When she said she liked her job but missed the full-time income, Kerns reportedly tossed a $100 bill at her and said, " 'There is more from where that came from.' "
"At some point between the time she drank the wine provided by Kerns and lost consciousness and the time she regained her memory as they entered her neighborhood, the victim has a vague memory of her head up against the car window and pushing Kerns away," the report reads.
She said that her recollection was foggy, but that the pair went back to her empty house, where Kerns assaulted her a second time. Her husband was out of town on business.
The grand jury also found that when Kerns and the woman entered her home, she went to the bathroom, emerged and collapsed onto her bed " 'like a wet noodle,' " in her words. She claimed that she vaguely remembered Kerns fondling her in bed and moaning. She told police that she awoke the next day bewildered, injured, covered in vomit and naked from the waist down.
Noticing red marks, bruising and scratches on her inner and outer thighs and vaginal injuries that lasted the weekend, the woman resigned from her job that Monday and called police.
According to the grand-jury findings, when asked why she waited several days before reporting the incident to police, she said she "was processing the shock over the weekend. . . . I guess I was very concerned with Bob's status and how I believe he will drag my name through the mud to make me look bad and protect his reputation."
When police executed a search warrant of Kerns' 2011 black Mercedes-Benz S550 in the days that followed, they found traces of evidence that corroborated the victim's story. Under the flooring of the trunk of the car, police recovered pink duct tape, an open bottle of Grey Goose vodka, lip balm and K-Y Warming Jelly.
A urine sample taken from the victim tested positive for Ambien, a prescription sedative commonly used to treat insomnia.
Detectives also reportedly recovered Kerns' DNA from the woman's underwear.
"The grand jury finds probable cause to believe that Robert Kerns plotted and planned to drug the victim to render her unconscious so that he would be capable of sexually assaulting her without her knowledge and regardless of her will," the report reads.
"Kerns believed he could take any sex act he wanted from his victim, without her consent, and she would never remember the details. We believe his expectation was that she would never know what happened after being drugged and therefore never make a report to the police."
The alleged incident occurred the night after Kerns attended a highly publicized county dinner at which he and other GOP heavyweights proudly announced a truce and a unified front, purporting to end a decades-long icy relationship among party leaders.
Kerns is married with three adult children. He had served as GOP chairman since 2008.
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