In testimony , Dr. Smithers said he was duped by some of his patients, many of whom told him pain clinics near them had already been shut down. “I learned several lessons the hard way about trusting people that I should not have trusted,” he said.

Dr. Smithers did not accept insurance; prosecutors said he had collected $700,000 in cash and credit card payments through March 2017, when federal agents raided his office. Patients who came to the office, which was often open past midnight, would wait as long as 12 hours to see him, prosecutors said, in order to obtain pain medication they could abuse or sell for profit.

Image Dr. Joel Smithers Credit... Southwest Virginia Regional Jail Authority, via Associated Press

In May, a jury found him guilty of 861 federal drug charges at the United States District Court in Abingdon, Va. Among those were one count of maintaining a place for the purpose of illegally distributing controlled substances and one count of possession with the intent to distribute controlled substances.

Martinsville, a city of about 13,000 near the North Carolina border, has one of the highest rates of opioid pills prescribed per person in the country. Dr. Smithers was visited by patients from West Virginia, Kentucky, Ohio, Tennessee and Virginia, law enforcement officials said.