IN A TENSE cross-examination, the Bucks County doctor accused of running a pill mill with the Pagans Motorcycle Club traded verbal blows Thursday with an FBI agent over matters ranging from alleged perjury to oral sex.

William J. O'Brien III, who's acting as his own attorney, is facing federal charges in a Philadelphia courtroom that he illegally distributed narcotic painkillers.

Prosecutors called FBI Special Agent Joshua Gill to testify about prescriptions O'Brien had written out to several of his patients and display those records to the jury.

O'Brien then had an opportunity to cross-examine Gill. The 51-year-old La Salle University graduate questioned whether the lawman had misspoken in a deposition prior to O'Brien's indictment.

O'Brien asked Gill if he had misstated during the deposition that Angela Rongione, O'Brien's former secretary, was working in O'Brien's Bustleton office at the time of the indictment - even though she had resigned in November 2014. Rongione had also been charged with illegally distributing narcotic painkillers, and was indicted with O'Brien in January 2015.

Following a tense exchange, O'Brien accused Gill of perjury after he said he didn't know if he had misspoken during that deposition.

"Would you ever lie to this jury?" O'Brien asked Gill.

"No," he replied.

"Would you lie to a grand jury?"

"No."

The FBI agent noted several times during the cross-examination the basics of the case against O'Brien - from allegedly falsifying medical records to prescribing medicine to patients without conducting examinations.

Gill also mentioned how O'Brien had asked an FBI agent, posing as an undercover patient, for oral sex in exchange for narcotic painkillers. After O'Brien asked Gill if he was in a federal trial because he asked for oral sex, Gill said it was one of many reasons the doctor had been indicted.

"I didn't ask for [oral sex] from anybody in exchange for painkillers," the FBI agent later quipped at O'Brien.

"I wouldn't take [oral sex] from you," O'Brien shot back.

O'Brien consistently grilled Gill about his medical knowledge involving painkillers, prescription dosages, and how those prescriptions are dealt out. Madison West, who identified herself as a legal spokeswoman for O'Brien, said he is fighting despite having to represent himself in the case.

"There's a lot of things that are being alleged," she said. "At the end of the day, he's doing the best he can . . . He's a doctor, not a lawyer."

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