In 2009, a 21-year-old woman accused Harvey, a seven-year veteran of the police force, of ordering her to strip naked and watch him masturbate while he and other members of the 24th District raided an abandoned Kensington house.
She and a friend were in a second-floor bedroom at the time, high on heroin and about to have sex, the woman testified at a 2011 hearing in Common Pleas Court. When he finished, Harvey threw six dollars in her direction and told her to buy herself some cigarettes, she said.
Her name has been withheld because The Inquirer does not identify victims of sexual assault without their permission.
But the case against the former officer seemed to sputter from the start, despite the woman's accusation and a semen sample taken from her pants that investigators say they linked to Harvey.
First, a judge declared a mistrial in the case after an assistant district attorney improperly referenced the pants, which had not been introduced into evidence. He later reversed his decision.
Then, state prosecutors missed their seven-month window to bring their case against Harvey.
In an opinion dismissing the charges last year, Common Pleas Court Judge Barbara A. McDermott blasted their tardiness despite "an extensive investigation resulting in solid physical evidence."
"There is simply no excuse for the Commonwealth's failure to resolve this matter before now," she wrote.
The District Attorney's Office has appealed that decision, most recently to the Pennsylvania Supreme Court.
In an interview Wednesday, Harvey's lawyer, James Funt, suggested the federal case stemmed from investigators' frustration over McDermott's decision.
He declined to comment on the specifics of the new case, saying he had not had a chance to review the indictment.
Cahill also testified at the 2011 hearing, but the story he told then differed significantly, according to federal court filings.
He maintained that he was with Harvey throughout the raid and that his fellow officer never had an opportunity to assault his accuser - a version of events federal prosecutors now call a lie.
On Wednesday, Police Commissioner Charles H. Ramsey suspended Cahill for 30 days with intent to dismiss.
The 10-year police veteran, who faces up to five years in prison if convicted, could not be reached for comment. It was unclear Wednesday whether he had retained an attorney.
Harvey, who until Wednesday had remained free on bond, faces a potential prison term of one year.