On Tuesday, a Texas jury found Eddie Ray Routh, accused of shooting Navy SEAL Chris Kyle and his friend Chad Littlefield, guilty.

Routh now faces life in prison for the murders he committed almost two years ago.

An Erath Count jury spent less than three hours deliberating their decision once closing arguments had been said, reports the Star-Telegram. The guilty verdict was read at 9:20 p.m. Tuesday night, and Routh, 27, was automatically sentenced to life in prison without parole.

Routh's defense team had hoped for a not guilty by reason of insanity verdict, arguing the former Marine suffered from PTSD and schizophrenia.

By contrast, the prosecution argued Routh knew what he was doing and was intoxicated at the time of the shooting.

Following the verdict's announcement, Kyle's stepfather, Jerry Richardson, and Don Littlefield, Chad Littlefield's father, addressed Routh.

"Because of you and your irresponsible choices, we lost a great son, brother, father, husband and uncle on Feb. 2, 2013," Richardson said. "You took the lives of two heroes -- men who tried to be a friend to you. You became an American disgrace."

Don Littlefield explained his son was trying to help him as well as other veterans.

"You confessed that you did not know his name when you brutally murdered him," Littlefield said. "You will have the rest of your wasted life, each and every day, to remember his name. Let me remind you. His name was Chad Littlefield."

Judy Littlefield, Chad Littlefield's mother, said she was "thrilled" by the verdict.

Kyle's wife Taya was not in the courtroom when the verdict was read, according to The Associated Press. The Kyle family did not issue a statement to the press.

On Feb. 2, 2013 Kyle and Littlefield took Routh to a shooting range after Routh's mother asked Kyle to help her son. Routh shot the two at the range. The defense argued Routh was insane and provided as evidence part of an interview with a New Yorker reporter.

"Are you gonna shoot? Are you gonna shoot? It's a shooting sport. You shoot," Routh said in the phone call, explaining the fact that Littlefield was not shooting bothered him.

The defense argued Routh believed the men would kill him, so he shot them first.

Two psychologists gave differing opinions on Routh's mental state. Dr. Randall Price, testifying for the prosecution, argued Routh had "substance-induced psychotic disorder" from heavy marijuana use. However, Dr. Mitchell Dunn disagreed on what caused his "psychosis."

"It is my opinion that he was suffering from a severe mental disease or defect that caused him not to know his conduct was wrong," Dunn testified.

Despite their best attempts, the defense did not succeed.

On Facebook, former Navy SEAL Marcus Luttrell, who befriended Kyle and is himself the inspiration for the film "Lone Survivor," said justice was served for Kyle and Littlefield. He also warned Routh.

"To Eddie Ray Routh, you thought you had PTSD before .?? Wait till the boys in TDC Find out you killed a TX hero," he wrote, referencing the Texas Department of Criminal Justice, which oversees prisons.