Sonnier was found dead Lubbock home on July 11th, 2012. Authorities have also charged Dr. Thomas Dixon, of Amarillo, for the murder, as well.
According to the arrest warrant, police believe Dixon hired Shepard to murder Sonnier. The warrant goes on to detail how Shepard told his roommate he had been watching Sonnier for weeks leading up to his death, and then also described how he broke into Sonnier's home and shot him multiple times.
The two men were indicted on capital murder charges in August 2012, and have been held in the Lubbock County Jail on $10 million dollar bonds since their arrests. Lubbock District Attorney Matt Powell said in July 2013 that capital murder charges could mean either the death penalty or life in prison without parole, although the DA's office has not made a decision.
Sentencing for Shepard will happen in the next few weeks.