EASTLAND, Texas (CN) - In the year since Eddie Ray Routh was convicted of murdering "American Sniper" Chris Kyle and his friend Chad Littlefield, his quest for a new trial has slowly wound its way through a Texas appellate court.
A state jury on Feb. 24, 2015 convicted Routh of the double murders of Kyle, 38, and Littlefield, 35. His victims had tried to befriend the ex-Marine, seeing him as a troubled, fellow veteran. Routh, then 25, murdered them at an upscale shooting range outside Dallas on Feb. 2, 2013, riddling them with 13 gunshots, then fleeing in Kyle's truck.
The trial came two years later, as the Clint Eastwood-directed movie "American Sniper" worked its way toward $500 million at the box office, based on the autobiography by Kyle, a former Navy SEAL who was said to be the most lethal sniper in U.S. history.
After a nine-day trial, it took the jury of 10 women and two men just 2½ hours to reject Routh's insanity plea and convict him of capital murder. He was automatically sentenced to life in prison without parole. The trial was held in Stephenville, the seat of Erath County.
Routh is incarcerated at the Louis C. Powledge Unit, a medium-security prison in Palestine, Texas, that also houses the fundamentalist religious leader and child rapist Warren Jeffs, who also is serving a life sentence.
Routh's attorney continues to insist his client was insane.
In a December brief to Texas' 11th District Court of Appeals in Eastland, Ft. Worth attorney Warren St. John says Routh was insane at the time of the crimes and "did not know his conduct was wrong."
St. John seeks reversal and a new trial based on two rulings by 266th District Judge Jason Cashon.
"It is clear the appellant met his burden of proof to show that he was insane at the time of the offense, but the jury chose to disregard Mr. Routh's severe mental illness," the 66-page appeal states.
"Dr. Price, a State's Expert, came up with some far-fetched idea that indicated that Mr. Routh's behavior was based on smoking wet marijuana. [But] Texas Department of Public Safety's chemist stated the marijuana smoked by Routh on February 2, 2013 was not laced with anything."
Prosecutors claimed Routh had a habit of faking symptoms to bilk the system, and that he knew what he was doing when he shot the men in the back. He admitted he killed them, then stole Kyle's truck and eventually led police on a high-speed chase, the prosecutors said.
Much of the trial centered on Routh's smoking habits, including his use of "wet marijuana"- marijuana soaked in embalming fluid. Erath County District Attorney Alan Nash and Assistant Attorney General Jane Starnes told the jury that the troubled veteran was a heavy marijuana user who suffered from cannabis-induced psychosis and alcohol abuse.
They acknowledged during closing arguments that Routh was "a weird, weird guy ... but that's not mental illness."
Routh's attorneys said he suffered from schizophrenia and post-traumatic stress disorder, and that when he killed Kyle and Littlefield he was in the grip of a psychosis "so severe that he didn't know what he was doing was wrong."
They presented experts who testified that Routh believed Kyle and Littlefield were "pig assassins," that his neighbor was a member of the Mexican Mafia who ate his excrement through the pipes, and that his girlfriend was a pig hybrid.
Routh did not testify.
The appellate brief claims the jury should not have heard statements Routh made to a Texas Ranger investigator immediately after the murders because he did not understand that he could terminate the interview.
"Mr. Routh was in a psychotic state," the appeal states. "The officer used a method to induce the appellant to give a statement that was in violation of the due process clause of the state and federal Constitutions."
The appeal also claims the judge abused his discretion by refusing to grant a mistrial when the prosecutor "paraded a vial in front of the jury that was not entered into evidence."
The jury was instructed to disregard the vial, but St. John said that instruction did not cure the harm created by the prosecutor.
Prosecutor Starnes concluded the state's case at trial by saying Routh murdered the two men in a way "that was calculated and that was cold. It wasn't accidental."
She said Routh fired two more shots into Littlefield as he lay twitching in a pool of blood and after firing six deadly shots at Kyle.
"This was not to prevent him from getting up, but to finish him off," she said. "He didn't want Chad dead. He wanted Chad dead, dead, dead, dead, dead, dead. And he wanted the same for Chris."
After hearing the verdict, Routh stood apparently emotionless, as he had throughout the trial, as he did as Kyle's and Littlefield's relatives made their impact statements.
"You took the lives of two heroes and you became an American disgrace," Littlefield's half brother Jerry Richardson told Routh before deputies ushered him out of the courtroom.
St. John seeks oral arguments before Texas' 11th Court of Appeals. Prosecutors have until March 11 to file a response.Follow @@eidelagarza
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