MEMPHIS (AP) — A Tennessee doctor who pleaded guilty to causing the overdose death of a patient by illegally prescribing the painkiller hydrocodone has been sentenced to 20 years in federal prison.

Thomas K. Ballard III was one of 53 medical professionals in the U.S. who were indicted in April 2019 on federal charges related to the illegal prescribing of painkillers. He was sentenced Tuesday, the U.S. attorney's office said in a news release.

Ballard, 63, operated the Ballard Clinic in Jackson. Ballard prescribed addictive drugs without any legitimate medical purpose and "engaged in inappropriate sexual contact with several female patients while he ignored red flags that they were abusing the medications he prescribed," the U.S. attorney's office said.

Ballard ignored one patient's past problems with drugs and psychiatric issues when he prescribed medications for her, including the opioid hydrocodone.

Ballard issued the patient a hydrocodone prescription in May 2015 — before she fatally overdosed.

Ballard pleaded guilty in June.