The defense called to the stand today a psychiatrist who interviewed Eddie Ray Routh, who allegedly shot and killed former Navy SEAL Chris Kyle and Kyle's friend Chad Littlefield at a Texas gun range in February 2013.
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Dr. Mitchell Dunn, a board-certified psychiatrist at Terrell State Hospital in Texas, interviewed the defendant for six hours last spring -- an abnormally long interview, he said.
One month before the shooting, Routh said he believed his co-workers at the cabinet company were cannibals and wanted to eat him, Dunn recalled from his interview. Routh also said he believed his neighbor, a police detective, was a member of the Mexican Mafia, Dunn recalled.
"Mental illness is not the way it is portrayed in movies," Dunn said.
Routh also told Dunn that he thought pigs were taking over the world. Routh said he thought his co-workers and ex-girlfriend Jen Weed were "pig hybrids" -- half man and half pig -- Dunn recalled, adding that Routh also described Kyle and Littlefield as "pig assassins."
When Kyle picked up Routh on the day of the shootings, Routh said he was upset that Kyle didn't introduce himself or shake his hand, Dunn said.
And Routh called the drive to the gun range a "one-way trip," Dunn recalled.
At the gun range, Routh wanted to neutralize what he perceived as a threat, Dunn testified, so he shot Littlefield first, and then when Kyle began to turn around, he shot him in the back.
Routh claimed he acted in self-defense, according to Dunn.
During the prosecution's cross-examination of Dunn, the psychiatrist said it was his expert opinion that Routh did not suffer from PTSD, only mental illness.
Jodi Routh, the mother of the accused killer, was also back on the stand today. When a prosecutor asked if she disclosed to Kyle that her son had been in the hospital just weeks before she arranged their meeting, she said, "it didn't occur to me at the time."
Kyle, who was helping war veterans after he retired as a Navy SEAL sniper, had agreed to help Routh that day at the gun range in February 2013.
Earlier today, the defense called Charles Overstreet, who has a Ph.D. in clinical social work and assessed Routh in jail. Overstreet said he believes Routh suffered from symptoms of paranoid schizophrenia and post-traumatic stress disorder, and that he thinks Routh misinterpreted Kyle and Littlefield's behavior as "threatening."
The prosecution objected to Overstreet's testimony, leading to a sidebar. Then the judge ruled that Overstreet could not testify for the jury.
Kyle, who was considered the deadliest sniper in U.S. military history, served four tours in Iraq and helped found a veterans organization.
He also wrote a best-selling autobiography, which served as the basis for the film "American Sniper," starring Bradley Cooper. "American Sniper" is up for six Oscars at this weekend's Academy Awards, and its popularity played a role in jury selection earlier this year.