Chris Kyle Texted "this dude is straight up nuts" About Shooter On Day He Died

Opening statements in the trial of Eddie Routh, the former Marine accused of murdering "American Sniper" Chris Kyle and Kyle's friend Chad Littlefield focused on the limited ground over which the case will be decided -- whether or not Routh met the Texas standard for legal insanity when he shot Kyle and Littlefield in February 2013.

Routh's defense team presented text messages sent between Kyle and Littlefield while in route with Routh to the shooting range near Glen Rose where they would die. "this dude is straight up nuts," Kyle told Littlefield, before Littlefield replied that Kyle should ""Watch my 6," meaning his back.

Routh's lawyer, Tim Moore, said Routh was in the midst of a psychotic episode during the shooting and outlined the treatment for mental illness Routh had received. He called Routh a "troubled vet" whom he was proud to represent.

See also: Why Did Chris Kyle Call Himself an "American Sniper," and Why Were We Cool With It? Chris Kyle's Widow Tells Glenn Beck She Doesn't Believe Her Husband's Alleged Killer Suffered From PTSD

Prosecutors pointed to the whiskey and pot Routh used before the shootings, and his actions after them, as evidence that he knew right from wrong.

After shooting Kyle and Littlefield, prosecutors said, Routh stood over their bleeding bodies, reloaded Kyle's 9 mm handgun and stole Kyle's truck before going to see his uncle. Routh left the .45 he shot Kyle with at the scene, Erath County District Attorney Alan Nash said. Kyle was shot five times in the back and once in the side of the head. Littlefield took four bullets to the back and one to face and the top of the head.