STEPHENVILLE, Texas (CN) - Attorneys for the Texas man charged with killing "American Sniper" Chris Kyle and his friend began mounting their insanity defense Tuesday by calling the murderer's mother to the stand.
Eddie Ray Routh is being tried for capital murder in rural Erath County, where jurors have heard prosecutors describe the 27-year-old former Marine as a deliberate killer who admitted shooting former Navy SEAL sniper Chris Kyle, 38, and his friend Chad Littlefield, 35, in February 2013.
Prosecutors rested their case Tuesday morning after jurors heard more than 25 prosecution witnesses testify about the slayings, including officers who investigated the crime and members of the victims' and defendant's family.
Kyle and Littlefield were gunned down by the then-25 year-old Marine veteran at an upscale shooting range outside Dallas. A 23-year-old gun range employee found the two friends with a total of 13 gunshot wounds.
Routh's attorneys say he is not guilty by reason of insanity.
Prosecutors told the jury of 10 women and two men that he intentionally shot the two men to death with two pistols, then stole Kyle's Ford truck and led police on a high-speed chase.
Routh's mother, Jodi Routh, testified Tuesday that her son was paranoid and suicidal. Routh served in Iraq with the Marines and later took on a rescue mission in earthquake-ravaged Haiti in 2010 that defense attorney Tim Moore said turned him into "a changed guy."
Jodi Routh facilitated the fatal encounter with her son after reaching out to Kyle for help with Routh's difficulty adjusting back to civilian life. Family members say Routh suffered from severe mental illnesses, including post-traumatic stress disorder.
Attorneys say Routh had been in and out of Veteran's Administration hospitals since 2011, having been diagnosed with psychosis and severe mental illness.
Jodi Routh said her son was released from a mental health facility 10 days before the murders, despite her pleas for him to remain in treatment.
If convicted, Routh will likely be sentenced to life in prison without possibility of parole. Prosecutors have indicated they will not seek the death penalty.
Kyle is famous for being the most lethal sniper in U.S. history. He is played by Bradley Cooper in the Clint Eastwood-directed movie depicting his life, based on Kyle's 2012 autobiography. It has grossed nearly $300 million at the box office since its December 2014 release and earned six Academy Award nominations.
Testimony was to resume Wednesday morning in Stephenville.