Prosecutors call William J. O'Brien III a pill-mill kingpin - a doctor who led a multimillion-dollar drug-distribution network with help from strippers and an outlaw motorcycle gang.

A federal judge called him a predator who contributed to the nation's opioid epidemic through profligate use of his prescription pad.

And plenty of federal court-watchers had occasion to call him a fool as he represented himself at a trial this summer with an unorthodox defense that included asking a witness to read Dr. Seuss' The Cat in the Hat from the witness stand.

But as O'Brien, 51, was sentenced to 30 years in prison Wednesday, the Bucks County doctor described himself as an honest professional who simply made a few mistakes - including prescribing a cocktail of drugs that left one of his patients dead.

"It's called 'a practice,' " he said of his medical career, "not 'a perfect.' I did the best I could as a doctor."

O'Brien, who has been in custody since his arrest last year, showed no remorse - a stance the court came to expect from the pain-management practitioner after his six-week trial.

He loudly proclaimed his innocence as U.S. District Judge Nitza Quiñones Alejandro handed down his punishment for 123 counts including drug trafficking, money laundering, and lying in a bankruptcy proceeding.

O'Brien's sentencing came four months after the federal jury found that he, together with members of the Pagans motorcycle gang, raked in $5 million over three years by recruiting fake patients, writing them bogus prescriptions for oxycodone, methadone, Xanax, Percocet, and similar drugs, and later selling the pills on the street.

O'Brien let the Pagans have full run of his office in Levittown, letting men with nicknames such as "Redneck," "Body Parts," and "Tomato Pie" monitor patient charts, schedule appointments, and provide security. When female patients were short on cash, he traded prescriptions for oral sex.

O'Brien's "actions have perpetuated the opioid epidemic plaguing our country," said Assistant U.S. Attorney M. Beth Leahy. "He may not appear menacing when compared to his Pagan accomplices, but he is every bit as dangerous, and no one should be fooled."

Still, his punishment could have been worse. Citing the trail of addicted patients and heartbroken families he left in his pursuit of profits, Leahy pushed the judge to sentence O'Brien to life in prison.

O'Brien said he could imagine fates far worse than that.

With a glance toward his ex-wife, who said Wednesday that O'Brien owed her thousands of dollars in alimony, he told the judge, "The only sentence that I can't abide by is to have to wake up next to her every day. Every day I spend in prison is better than a day spent with her."

Later, as the judge ordered that he pay $342,500 in restitution to creditors in his ongoing bankruptcy case, O'Brien turned, locked eyes with his ex-wife in the courtroom gallery, and mouthed with a smile: "Not a penny."

Making a scene

Court observers had grown used to such antics.

For nearly six weeks of trial this summer, he held Quiñones' courtroom a virtual hostage as he made himself out to be the victim of an unscrupulous investigation by federal authorities who didn't know the first thing about medicine.

He lobbed impudent questions at agents during his cross-examinations, asking one if her current boyfriend was the father of her "love child," and informing another that he wouldn't accept oral sex from him if it was offered.

He challenged one government witness - a tattooed Pagans associate with a thick South Philadelphia accent - on his grasp of the English language by having him read excerpts from The Cat in the Hat to the court.

As jurors looked on with disbelieving stares and fits of guilty laughter, O'Brien took advantage of every inch of leeway the judge was willing to give him.

Victims and families

But Wednesday's sentencing exposed the vein of tragedy underlying the circuslike atmosphere of his trial.

Before announcing the sentence, Quiñones heard from former patients and their families, including a former heroin addict, who was six months pregnant with track-mark-scarred arms when O'Brien offered to write her a prescription in exchange for oral sex.

"You're nothing more than an addict yourself," the woman said, citing the doctor's pursuit of profits.

Bridget Shaw detailed how her brother Joseph Ennis died while being treated after being hit by a van while walking in a snowstorm. He was found dead in December 2013 at the age of 38.

"Our brother was not an addict. He was a patient relying on you for help," she told O'Brien. "Joey was trusting you would safely take his pain away, and you stopped his heart."

The unrepentant O'Brien jabbed back - calling out each prosecutor and investigator by name, and blaming his patients for decisions that led them to overdose or sexually debase themselves for drugs.

As he prepared to spend the next three decades of his life behind bars, O'Brien offered a promise to prosecutors.

"This isn't even near done yet," he said, vowing to appeal. "This was just a first step."

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