So, according to the article, she went with her son, who was armed, to hunt down the road rage guy, now shooter, found him and then lost him. Then the shooter, followed them back to their home where he murdered her there in self defense
Sounds like Saturday night in white trash land
He followed her to her house, armed with the intent to do great bodily harm. Regardless of reason, that is voluntary manslaughter or premeditated murder. A vehicular accident, even an assault or road range incident, is not justification for voluntary manslaughter or premeditated homicide.