Texas jury finds ex-Marine guilty of killing "American Sniper" author Chris Kyle

The jury in the trial of Eddie Ray Routh, an ex-Marine charged with killing "American Sniper" author Chris Kyle and another man, has found him guilty of capital murder.

Jurors returned the verdict Tuesday night, convicting Routh of killing both Chris Kyle and Kyle's friend Chad Littlefield at a firing range southwest of Fort Worth, Texas in February 2013. The judge read the verdict, and then polled the jury, all of whom affirmed the guilty verdict.

Routh was immediately sentenced to life in prison without the possibility of parole.

Over the course of the trial, defense attorneys for Routh argued the 27-year-old suffered from a form of psychosis, while prosecutors painted him as a drug abuser who, despite any claims of mental illness, knew the difference between right and wrong.

The jury deliberated for a little more than two hours before reaching a verdict at a court in the rural Texas city of Stephenville.

In closing arguments before the case went to the jury, prosecutor Jane Starnes said Routh acted coldly and deliberately when he waited for Kyle to empty his gun at the range and then ambushed the two from behind before fleeing the scene Kyle's pickup truck.

Defense lawyers argued that Routh was a paranoid schizophrenic and should be declared innocent by reason of insanity.

"That is not insanity. That is just cold, calculated capital murder," Starnes said.