FORT WORTH — A jury convicted Jason Alan Thornburg of capital murder Wednesday evening for killing and dismembering three people in fall 2021 — murders prosecutors say he committed after befriending the victims and later told police were ritualistic sacrifices carried out at God’s command.
The guilty verdict came on the eighth day of testimony and after about two hours of deliberation. The jury rejected a request from Thornburg’s defense attorneys for a verdict of not guilty by reason of insanity.
A capital murder conviction allows for two sentences: life in prison without parole or the death penalty, which Tarrant County prosecutors are pursuing. The trial will resume at 10:30 a.m. on Thursday for the punishment phase, where the jury will determine Thornburg’s fate.
Over the span of a few days in September 2021, police and prosecutors allege, Thornburg killed three people — a man and two women — by slitting their throats or strangling them inside his room at the Mid City Inn in Euless.
On Sept. 22, Fort Worth firefighters discovered the bodies of David Lueras, 42, Lauren Phillips, 34, and Maricruz Mathis, 33, in a burning dumpster. The victims had been dismembered, their remains placed in plastic bags and bins.
The defense did not contest that Thornburg committed the killings.
Instead, defense attorney Bob Gill told the jury a combination of factors — Thornburg’s troubled childhood, including a heroin-using, neglectful mother who drank while she was pregnant with him, and his “crazy, whacked out” religious beliefs, particularly a “deeply entrenched delusion” that God had commanded him to kill — should result in a verdict of not guilty by reason of insanity.
During closing arguments, prosecutors cast Thornburg as a manipulator engaged in a yearslong “con” to evade responsibility for the killings. They described his “methodical” actions to dispose of the bodies as deliberate efforts of a sane man trying to destroy evidence.
“This crime is crazy. Yes, it is. No doubt about that,” Tarrant County prosecutor Emily Dixon told the jury. “He is not insane, though. There’s absolutely no doubt about that.”
At one point, prosecutor Kim D’Avignon showed the jury large photographs of Lueras, Phillips, and Mathis. She juxtaposed the photographs with a photo in evidence showing the condition of the victims’ bodies after they were discovered.
At least three members of the jury — 11 women and three men, including two alternates — appeared to wipe away tears. One juror looked away from the image.
Thornburg, whose jet-black hair has grown past his shoulders since his initial booking photo was taken more than three years ago, did not visibly react as Judge Douglas A. Allen read the guilty verdict aloud. People sitting in the courtroom in a section reserved for the victims’ family and friends let out a deep breath.
Thornburg, 44, is also charged with murder and arson in the death of his roommate. At the time of his arrest, Thornburg was being investigated in connection with the disappearance of his girlfriend, who was reported missing to New Mexico police in 2017.
According to an arrest warrant affidavit, Thornburg admitted to killing his roommate, Mark Jewell, 61, whose body was found after a gas explosion in May 2021.
Thornburg was also accused of killing his ex-girlfriend. A relative who spoke with the Fort Worth Star-Telegram identified her as Tanya Begay, an American Indian woman from Gallup, N.M., who went missing while on a trip with Thornburg.