Routh is one of the many Iraq veterans suffering severe mental problems, and Kyle was helping him cope. Kyle figured a good way to help Routh with his struggles was to take him to a gun range. It turned out to be a fatal decision. Routh opened fire on Kyle and another friend, killing them both. Routh is now in jail in Texas facing capital murder charges.

According to the New York Times, last September Routh threatened to murder his family and to commit suicide. He had gotten upset when his father threatened to sell his gun. Routh was arrested and taken to a psychiatric hospital in Dallas. He told the police that he was a Marine veteran suffering from post-traumatic stress disorder.