Stephenville, Texas (CNN)Even with a conviction, the "American Sniper" murder trial never answered the one question that still haunts the families of Chris Kyle and Chad Littlefield. Why were the two men killed while trying to help Eddie Ray Routh? There have been a series of confusing and incoherent explanations for Routh's motives the afternoon of February 2, 2013. We know Kyle sensed tension as he and Littlefield drove the former U.S. Marine to a gun range for an afternoon of bonding and helping Routh cope with what his family members believed was post-traumatic stress disorder. Kyle secretly texted Littlefield, sitting next to him in a pickup, to say Routh was "straight up nuts." Kyle's wife, Taya, "could tell something was up" that afternoon when she spoke to her husband. Kyle sounded "irritated," she has testified, then he never responded to a text asking if he was OK.
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The motive for Chris Kyle's killing remains unclear
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Routh provided a series of bizarre statements to explain the shootings
@placeholder was shot four times in the back and once in the face.
Routh's attorneys have suggested it was the arsenal of firearms lying next to @placeholder that triggered his psychosis and paranoia on the car ride.