FILE – This June 15, 2018, booking photo provided by the Westminster Police Department shows Jeremy Webster. (Westminster Police Department via AP,File)

By Colleen Slevin, The Associated Press

BRIGHTON — A Colorado man who shot and killed a 13-year-old boy after a road rage confrontation and wounded the boy’s mother, brother and a witness was found guilty of first-degree murder Wednesday.

A jury deliberated for less than three hours before issuing the verdict for Jeremy Webster, who was also found guilty of attempted murder and assault for the June 14, 2018, attack.

Webster told police that he was not in his body or in control of his emotions during the attack, and that he witnessed his “arm doing the shooting” as if he were an outside observer.

His lawyer, Rachel Oliver, said he had been losing his mind for years, and asked the jury to find him not guilty by reason of insanity, which would send him to a mental hospital for treatment.

“His mind betrayed him very early on and it continued all the way through June 14, 2018, and it is going to continue for the rest of his life,” she said, noting that Webster’s problems began at age 4, when he saw a psychologist for the first time. They worsened after he moved to Colorado as an adult and grew isolated, Oliver said.

But prosecutors said Webster was sane and acted deliberately and with intent, following Meaghan Bigelow and her sons to the parking lot of their dentist office after accusing Bigelow of cutting him off while he was headed to Home Depot. The two argued in the parking lot and Webster pulled out a gun after Bigelow used her phone to take a video of Webster’s car.

Webster, 28, sat in his chair at the defense table drinking from a water bottle when the verdict was read Wednesday and did not appear to show any emotion. Meghan Bigelow, seated next to her husband in the front row on the other side of court, cried and wiped away tears as the verdict was read.

Bigelow testified that she began walking away from her sons to keep Webster’s attention on her. After she was shot and lying on the ground, prosecutors say, Webster shot her 7-year-old son Asa in the back of the head, fired at her 12-year-old son Cooper as he ran to the dental office for help and then firmly pressed his handgun to the back of Vaughn Bigelow Jr.’s head, fatally shooting him. Prosecutors said the impression of the gun could be seen on Vaughn’s head.

“It doesn’t get more intentional and deliberate than that,” Chief Deputy District Attorney Jennifer Prince told jurors during the prosecution’s closing arguments.

After the shootings, Webster went to Home Depot to buy a new saw for a home renovation project he was working on for his cousin’s construction company. He returned to work on the project and was arrested by police after his car, identified with the help of Bigelow’s video, was spotted in rush hour traffic that evening.

The shootings happened about three months after Webster began taking medication for bipolar disorder and after he had stopped drinking and cut down on his use of marijuana, which Oliver said he had been using to self-medicate his mental illness. Shortly before the shootings, he had complained to his psychiatrist that he needed to adjust his medications because he was feeling paranoid, she said.

However, a court-appointed psychologist, Christina Gliser, who interviewed Webster twice, concluded that at the time of the shooting, he was sane as defined under Colorado law: able to make decisions and recognize the difference between right and wrong.

Gliser also testified that during testing, Webster tended to exaggerate his symptoms. She did not think he had bipolar disorder but instead diagnosed him with borderline personality disorder because he had emotional reactions to life stressors.

Webster told police who interviewed him hours after the shooting that he was disconnected from his body and watched his arm “do the shooting,” Gliser testified. But she said that claim was “likely inaccurate and untrue” since Webster did not have a long history of trauma that usually leads to that level of disassociation.

An expert hired by the defense, Dr. Richard Martinez, diagnosed Webster with schizoaffective disorder, bipolar type, but did not evaluate whether he was sane at the time of the shootings. Martinez, a psychiatry professor at the University of Colorado’s medical school who met with Webster four times, said he did not see a reason to doubt his description of feeling disassociated during the shooting, which he said would be hard to fabricate.

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