Jeremy Webster, 27, learned his sentence Wednesday after a Denver jury found him guilty of 12 violent crime counts.
Authorities say Webster became enraged with Meghan Bigelow in June 2018 after she pulled her car over for an emergency vehicle.
Webster took that move as a cut-off and started shouting obscenities, Bigelow testified during his two-week trial.
She said Webster followed her car to the parking lot of a dentist's office, pulled out a gun and fired several shots at her and her three sons.
Vaughn Bigelow Jr., 13, was hit in the head and killed. Brother Asa Bigelow, 7, was reportedly critically injured with brain and hearing damage. Another brother escaped unharmed.
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According to KCNC-TV, Webster told police he had mental health issues. His attorneys called it “schizoaffective bipolar disorder,” but a psychologist testified that Webster was sane.
“I’ve seen a lot of bad cases in my career, and this is one of the worst we have ever, ever seen,” District Attorney Brian Mason told KDVR-TV outside court.
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