David Shepard of Amarillo, Texas was found guilty of killing pathologist Dr. Joseph Sonnier. Shepard says he was hired to kill Sonnier by another Texas doctor, Shepard’s best friend Dr. Thomas Michael “Mike” Dixon, a plastic surgeon. Dixon’s motive was vengeance: his ex-girlfriend Richelle Shetina was dating Sonnier. Sonnier was found shot and stabbed to death in his home in 2012.
Dixon paid Shepard for the job with a box of Cuban cigars and three silver bars. Before the day of the murder, Shepard sold one bar at an Amarillo pawn shop. He sold the other two the day after. When caught, Shepard admitted that Dixon paid him to do it. He agreed to testify against Dixon as part of a plea to avoid the death penalty. But when Shepard got on the stand, he refused to answer questions. Both Shepard and Dixon are currently serving life sentences in jail. ABC 20/20 will air its investigative report on Friday, January 8 at 10pm.