Eddie Routh Attorney Says 'American Sniper' Didn't Hurt Case

A defense attorney for Eddie Ray Routh, who was convicted of capital murder in the "American Sniper" trial, said the fact that some jurors had seen the movie did not hurt their case.

The movie "American Sniper," which was up for six Oscars this past weekend, including Best Picture, is based on the memoir of famed Navy SEAL Chris Kyle, the most lethal sniper in U.S. military history.

A Texas jury of 10 women and two men found Routh guilty Tuesday of killing Kyle and Kyle's friend Chad Littlefield during a trip to a gun range Feb. 2, 2013. After the verdict, it was revealed that several members of the jury saw the movie before being selected to serve on the trial, but they maintained it did not interfere with their ability to fairly judge Routh.

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Attorney Shay Isham, who was part of the team that defended Routh, said in an interview with ABC News' "Nightline" that there were concerns about selecting jurors for the highly publicized case, but they didn't see the movie as a reason to dismiss them.

"I've been picking juries here for 19 years and in a whole lot of other counties, too. Just because someone has seen the movie doesn't automatically disqualify them," Isham said. "Most of the people that can do that job and can take an oath to not be leaning one way or the other, and wait until the evidence is finished to make up their mind and deliberate the case; most of them that tell me that, they can set that aside."

"There wasn't very many jurors dismissed because of too much pretrial publicity because they've seen so much or read so much that they already had their mind made up," he added. "You get 10 strikes in a criminal case in the state of Texas and so there's a whole bunch of things that go into whether you want to exercise one of those precious few strikes that you have."

Routh had pleaded not guilty by reason of insanity and his attorneys had argued the former Marine had mental disorders and was in the grips of psychosis when he fatally shot Kyle and Littlefield.

Because Routh's lawyers never disputed he killed the two men, the biggest question the jurors had to answer was whether they thought he was legally insane or whether he was faking his claims of insanity.

Seven members of the 12-person jury spoke to ABC News today about how they came to the unanimous decision after two and a half hours Tuesday night.

"That was something that we really had to figure out," juror Kristina Yager told ABC News. "In the beginning, I know a lot of us came into the jury questioning that, but evidence shows that there was a real definite pattern there."

"When I say there's a pattern that we saw, he would get intoxicated, get in trouble, and then the police would show up and he would say 'I'm a veteran, I have PTSD, I'm insane,' you know, and every time something bad happened he pulled that card," Yager said.

Routh's mental state was at the crux of the case, with both sides presenting experts who disputed different diagnoses up until the final hours of the trial.

While calling rebuttal witnesses to the stand Tuesday, the defense also re-called Dr. Mitchell Dunn, the psychiatrist who concluded Routh was insane in earlier testimony.

Isham, Routh's attorney, said he doesn't second-guess using the insanity defense for Routh.

"I don't think it was a gamble that the insanity defense was what we provided," he said. "[It was] the most viable defensive theory because of his trips to the [Veterans Affairs] mental hospital and Green Oaks mental hospital, and the diagnosis of schizophrenia. There were other experts also that thought he was legally insane."

And Isham added that PTSD was "never a part of the defense strategy."

"Mental illness was what he was diagnosed with, mental illness was what he went to the hospital for," he said.

Routh was sentenced to life in prison without the possibility of parole, but Isham said he expects an appeal to be filed in this case.