A disgraced doctor, testifying during the already lurid trial of former New Orleans police Officer Donald Nides, turned heads Tuesday when he acknowledged masturbating to child pornography and patronizing “whores in Holland” because he was too embarrassed by his sham pain clinics to seek relations with women in the United States.

“I guess I was ashamed of what I was doing,” Dr. Joseph J. Mogan III, a key government witness, told jurors on the second day of Nides’ federal trial.

Nides’ defense attorney, Arthur “Buddy” Lemann, pounced on Mogan’s extracurricular activities during cross-examination, arguing that the prosecution’s case rests upon the self-serving concoctions of two convicted felons seeking lenient sentences despite their admitted roles in a drug conspiracy.

Lemann noted that Mogan, in exchange for his cooperation, wasn’t prosecuted for possessing images of “underage girls in sexually explicit poses” on his computer.

When Mogan admitted that he hoped, in testifying against Nides, to avoid a decades-long stint in federal prison, Lemann said, “You want to be able to go back to Amsterdam and smoke pot and copulate with young underage girls.”

Mogan demurred, saying he intended to change his ways. “Hallelujah!” Lemann shouted, drawing an objection from Assistant U.S. Attorney Harry McSherry.

The dramatic exchange highlighted the challenges prosecutors face in calling to the stand two seemingly unsympathetic codefendants in their case against Nides, a veteran law enforcement officer who is charged with obstruction of justice, lying to federal agents and participating in a sweeping drug conspiracy.

McSherry sought to get out ahead of Mogan’s baggage, making no excuses for the doctor’s behavior during a lengthy direct examination and pointing out that he is headed for prison.

The prosecutor noted briefly that the freewheeling clinics had seen some patients overdose and even die.

“There were patients who were in there who were loaded,” Mogan said, adding that the lawman he knew as “Mr. Don” had been instrumental in helping the clinics avoid attention from law enforcement.

Nides, 64, who served in the NOPD for more than three decades and for several years was a deputized member of a U.S. Drug Enforcement Administration task force, is accused of taking bribes of cash and oral sex from Tiffany Miller Gambino, another operator of the clinics. In exchange, prosecutors allege, Nides gave Gambino frequent pointers on how to keep the cash flowing and to keep the clinics from attracting attention from the DEA.

Gambino, 43, is expected to tell jurors about the frequent “blow jobs” — a phrase Lemann has practically shouted at the jury — that she gave Nides in the kitchen of one of the clinics and, on occasion, inside his vehicle.

Mogan —who pleaded guilty alongside Gambino last week to money laundering and conspiring to dispense prescription pills, subjecting himself to a sentence of up to 40 years in federal prison — took the stand Tuesday dressed in a pinstripe suit and red tie.

Mogan, 47, who surrendered his medical license this year, walked the jury through his years as a doctor at Omni Pain Management in Metairie and Omni Pain Management Plus in Slidell, clinics he described as “pill mills” from their inception.

“I was greedy,” Mogan said, noting that the clinics, which accepted only cash, raked in about $1.5 million a year, an income that allowed him to own three Ferraris. “I did it for the money.”

Mogan admitted exploiting the addictions of his clients, writing prescriptions for patients without even examining them. Word spread among pill abusers that Omni was a reliable place to score a fix, Mogan said, and droves of patients flocked to it from long distances.

“It was a madhouse,” he said of the Metairie clinic. “We had up to 30 patients in the waiting area all at once.”

The operation, which ended last year, might have been shut down far sooner, prosecutors allege, if it weren’t for Nides, a DEA task force member who was supposed to keep a watchful eye out for illegal dealing in prescription pills.

Nides would give frequent guidance to Gambino that even affected the clinics’ prescribing habits, Mogan said. “He was helping us make money and stay in business,” he said.

Mogan said he noticed — and did not object to — the obviously intimate relationship Gambino fostered with Nides, in which the pair “chitchatted” and flirted on a regular basis, spending hours on the phone together. He often saw “Mr. Don” at the Metairie clinic, he said, and Nides and Gambino would lock the door in the kitchen for long periods of times, prompting staff members and patients to go down the street to other businesses to urinate because they couldn’t get to the clinic’s bathroom.

Mogan said he assumed the two were having sex. “It made me know that we were safe,” he said. “I gave them their privacy and just was able to keep it to myself.”

In early 2008, Mogan said he became concerned the DEA was closing in on the clinics — “I didn’t feel like we were doing anything for these patients,” he said — but he was assuaged by Gambino.

While smoking pot with Gambino at Mogan’s former nightclub on Tchoupitoulas Street, Mogan said he expressed concerns because he was afraid of going to jail. That’s when Gambino told him not to worry, he said.

“I’ve been paying Mr. Don off with cash,” Mogan recalled Gambino telling him. “I was relieved when I heard that.”

Jurors also heard Monday from George Cazenavette, a longtime DEA agent who previously led the agency’s New Orleans field office. Cazenavette testified that, when confronted, Nides acknowledged Omni was a pill mill but claimed it wasn’t his job on the task force to pursue such operations.

He said Nides claimed his only job was to seek out so-called doctor shopping by patients and that he developed a close rapport with Gambino because she was a reliable informant. However, Nides failed to point to a single prosecution that resulted from the relationship.

Nides is accused of lying to federal agents about his communications with Gambino, and prosecutors on Tuesday introduced dozens of call records that showed the two kept regular contact even after Nides had been removed from the task force and retired from the Police Department.

Nides adamantly denied having sex with Gambino and accepting bribes.

“He said he never had any kind of conversations with her about oral sex,” Cazenavette added, “and said if anybody said that they’re lying.”

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