A former Casper doctor and his brother are schedule to be sentenced in federal court in Cheyenne on Monday for their convictions in an multi-state prescription drug conspiracy.

Dr. Shakeel Kahn and his brother Nabeel Kahn were convicted of multiple crimes after a month-long trial in Casper that ended in May after an investigation that began more than three years ago.

Shakeel Kahn was convicted of 21 counts including conspiracy to distribute oxycodone and other drugs resulting in death, possession a firearm during a federal drug-trafficking crime, and operating a continuing criminal enterprise.

Depending on how judge Alan Johnson applies the federal sentencing guidelines, Shakeel Kahn could be sentenced to at least 25 to 45 years if not life imprisonment.

Nabeel Kahn, an office manager for his brother, could face at least five years imprisonment for possession of a firearm during a drug-trafficking crime.

Last week, U.S. District Court Judge Alan Johnson denied Nabeel Kahn's motion for a new trial.

Johnson wrote the prosecution presented sufficient evidence about Nabeel Kahn's involvement in the conspiracy, that he possessed a firearm during a drug-trafficking crime, and that he did not show his trial should have been separate from his brother's.

Shakeel Kahn would charge customers $500 or more for prescriptions of powerful painkillers that left many people addicted.

Three other defendants in the case pleaded guilty before the trial began. They were Shakeel Kahn's wife, Lyn, Paul Beland and Shawnna Thacker.