Dr. James Graves, the Milton, Florida physician accused of excessively prescribing the painkiller OxyContin, was convicted Tuesday of four counts of manslaughter, five counts of unlawful delivery of a controlled substance and one count of racketeering. Graves becomes the first doctor to be convicted of manslaughter in an OxyContin overdose case. He faces up to thirty years in prison.

Graves reportedly needed money after he was discharged from the Navy and fired from several medical positions. He testified that he had no knowledge of patients abusing the drug. OxyContin, a powerful opiate linked to hundreds of overdose deaths, produces a heroin-like high when crushed and snorted or mixed with water and injected.