Eddie Ray Routh confessed in jail to gunning down Navy SEAL sniper Chris Kyle and his friend because they would not talk to him during a long drive to a rifle range, a police officer has testified.
Gene Cole, a former patrol deputy in Erath County, revealed for the first time a possible motive in the case as he took the stand at 27-year-old Routh's murder trial in Stephenville, Texas, on Friday.
Dressed in his police uniform, he told the court: 'I heard Mr Routh say, "I shot them because they wouldn't talk to me. I was just riding in the backseat of the truck, and nobody would talk to me.'
He added that the former Marine believed Kyle and his friend, Chad Littlefield had forgiven him. '[He told me], "I feel bad about it, but they wouldn't talk to me. I'm sure they've forgiven me",' he said.
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Testimony: Gene Cole (pictured in court), a former patrol deputy in Erath County, testified on Friday that Eddie Ray Routh shot dead famed Navy SEAL sniper Chris Kyle and his friend because they would not talk to him
Defendant: Mr Cole told the court: 'I heard Mr Routh say, "I shot them because they wouldn't talk to me. I was just riding in the backseat of the truck, and nobody would talk to me.' Above, Routh in court Friday afternoon
Murder trial: Routh (pictured, center, during his capital murder trial in Texas) is accused of shooting dead the two soldiers at a shooting range in February 2013. The ex-Marine has pleaded not guilty by reason of insanity
Gunned down: Former Navy SEAL Chris Kyle, left, and his fellow veteran Chad Littlefield, right, were killed
Routh is accused of shooting dead the two soldiers at a Texas-based rifle range in February 2013. His attorneys have claimed the defendant, who had PTSD, was in a psychotic state at the time.
The killer has pleaded not guilty by reason of insanity. At the end of the trial, jurors must decide whether or not he intentionally committed the murders and knew that his actions were wrong.
On Friday, Cole, now a Belton police officer, said Routh confessed to murdering Kyle and Littlefield 'because they wouldn't talk to me' on June 22, 2013, more than four months after the killings.
At the time, Routh was an inmate at Erath County Jail.
After Cole's bombshell testimony - the first time a possible motive for the killings has been unveiled - Judge Jason Cashon halted proceedings for the day. Testimony will resume on Monday morning.
Earlier in the day, jurors heard that Routh gunned down Kyle and Littlefield, before stealing Kyle's vehicle and driving to his uncle's house, where he told the man: 'I'm driving a dead man's truck.'
Taking the stand, Routh's uncle, James Watson, described his nephew's actions in the wake of the murders - and also revealed how they had both smoked 'strong' marijuana before them.
Questions: Earlier in the day, jurors heard that Routh gunned down Kyle and Littlefield, before stealing Kyle's vehicle and driving to his uncle's house, where he told the man: 'I'm driving a dead man's truck.' Above, Routh's uncle James Watson (right) looks at photographs offered by the defense on Friday as he testifies
Evidence: Texas Ranger David Armstrong holds up evidence seized at Routh's home. During his testimony, he said drug paraphernalia and marijuana was found inside this Hershey's box
Found: He also holds up a hookah pipe, left, and a box of 9mm pistold ammunition, right, found at the home
Watson, 45, told the court how Routh had struggled to find a full-time job and 'didn't seem to find much joy in his life after he came back' from serving in Iraq and Haiti.
On February 2, 2013, Watson said he smoked weed with his nephew, who had just argued with his then-girlfriend, and they chatted about his relationship troubles.
'His work situation and his relationship were the two main things upsetting him that morning,' he said. Authorities have said they believe Routh also consumed whiskey before leaving the house, but Watson said it was uncommon for them to drink in the morning.
'I don't remember drinking whiskey that morning, but it doesn't mean I didn't,' he said.
Still, the marijuana was strong, he said, and his buzz lasted around three hours.
Search: Erath County District Attorney Alan Nash points to a diagram of former Routh's Lancaster, Texas, home while questioning Ranger Armstrong, who said they also found alcohol and psychotic medicines inside
Surrender: Routh eventually stops and surrenders and climbs out of the car with his hands raised
About 90 minutes after smoking, Routh was picked up by Kyle and Littlefield and they went to the shooting range. While there, he shot both men in the back, killing them, and then stole Kyle's truck.
When he arrived at his uncle's home and said, 'I'm driving a dead man's truck', Watson misinterpreted 'dead man' as Routh himself, he said.
'He thought people were out to get him,' Watson testified.
Routh also showed his uncle a black 9mm handgun, which was owned by Kyle and which he used to kill Littlefield at the range of Rough Creek Lodge and Resort, authorities have said.
There is no doubt over the fact that Routh was responsible for shooting Kyle, a married father-of-two with the most kills to his name in U.S. military history, and his friend.
Arrested: Nash holds up an image of Routh handcuffed in the back of a police car on the night of his arrest
Instead, the defense and prosecution are trying to prove whether or not he was driven by mental illness when he carried out the murders.
Also on Friday, a ranger testified that he found whiskey, drug paraphernalia and medicine for schizophrenia in Routh's home the day of the shootings - giving some insight into his troubled life.
I heard Mr Routh say, "I shot them because they wouldn't talk to me. I was just riding in the backseat of the truck, and nobody would talk to me
Ranger David Armstrong told the court that he discovered a nearly-empty bottle of whiskey, an empty glass and drug paraphernalia, including bongs, pipes, a grinder and marijuana.
He also found a prescription drug,
Risperidone, used to treat psychosis, bipolar disorder and schizophrenia, but defense Attorney Tim Moore told the court it had not been collected as evidence.
Rangers also found 'an assortment of firearm ammunition' inside Routh's guest room - as well as Chris Kyle's name and number written down and pinned to his fridge, Armstrong said.
Although the prosecution suggesed that Routh had been numbed by alcohol or marijuana at the time, Armstrong said Routh had not smelled of either after his arrest.
Instead, he claimed in court that the home smelled of marijuana - although this was not included in his report at the time.
Chris Kyle's widow, Taya Kyle, greets a supporter before court is in session on Friday
Support: Taya Kyle, who testified in the trial earlier this week, hugs a reporter before the proceedings
Kyle's widow, Taya, was in the courtroom again on Friday. Earlier in the week, she gave emotional testimony about the last time she ever spoke to her husband.
On Thursday, prosecutors showed the jury a never-before-seen video of the moment Routh tried to speed away from authorities before he eventually surrendered.
The video shows Routh driving Kyle's truck, which he stole after shooting the men in their backs at a Texas driving range, before speeding away from police officers, who trail him for nine minutes.
Former Marine: Routh, pictured in court on Friday morning, served in Iraq as a small arms technician
But as he nears Interstate 35E and Interstate 20, he is forced to stop due to a technical difficulty - and he can be seen emerging from the vehicle with his hands raised as officers swoop on him.
Body camera footage also shows police officers pleading with Routh to get out of the truck for 30 minutes before the chase.
His attorney has suggested Routh, who was suffering from post-traumatic stress disorder, was in a psychotic state and thought Kyle and Littlefield were going to kill him.
'Is the apocalypse upon us right now?' Routh can be heard saying on the body-cam recording.
The 27-year-old also talked about voodoo, hell, and the apocalypse, and wondered aloud to the cops: 'I don't know if I'm going insane.'
At different points in the video, Routh made comments including, 'I didn't sleep a wink last night at all,' 'I don't know if I'm going insane,' and, 'Is this about hell walking on earth right now?'
In court, Lt Michael Smith testified that Routh said something to the nature of: 'He had taken a couple souls and he had some more souls to take.'
'Everything's just happening so fast...I don't know if I'm going insane,' he told the police officer.
'That's what we need to figure out,' the officer responded. 'We need to figure out what you're thinking and then see if it's right or wrong.'
He eventually sped away from officers.
Routh's defense attorney R. Shay Isham argued that his client's ravings served as proof that he was out of touch with reality that night - but prosecutors have argued that the fact he drove away, and had earlier stopped at a Taco Bell drive-thru for two burritos, showed he was of right mind.
As the videos played in court on Thursday, Littlefield's relatives sobbed, while Kyle's widow Taya shook her head,
ABC reported.