But some of the doctors receiving payments had messed up so bad that they had their medical licenses revoked (40) or suspended (180). Another 250 had been placed on probation.

Some of the severe offenses include sexual misconduct, overcharging Medicare or Medicaid, and providing negligent care.

Another severe offense highlighted in the report is inappropriate prescriptions. A number of physicians have been sanctioned for providing powerful, addictive painkillers without good cause.

Keep in mind, it is generally acknowledged that the entire U.S. health care system has been asleep at the wheel on the issue of opioids. But one of the physicians highlighted in the report, for instance, prescribed oxycodone to a patient who he had never treated after a mere phone call, in violation of New York state regulations.

"I think it's crystal clear that their fiduciary duty is not to educate physicians and make public welfare better. It's to sell a product," Charles Rosen, president of the Association for Medical Ethics, told ProPublica. "I think they'd pay the devil if no one knows and he sells a lot."

The issue of pharmaceutical companies and device manufacturers paying for doctors has become increasingly controversial in recent years, with many hospitals imposing strict rules forbidding employees from accepting payments or gifts from industry representatives. A survey last year found a sharp uptick in the number of doctors that were identified as inaccessible to pharma reps.

Companies have tried to get around such rules by sponsoring lunches or other events that are framed as educational and may not involve overt promotion of the sponsor. A study found that even a free meal appears to have a noticeable effect on a doctor’s prescribing habits.