The local press is reporting that there have been a number of domestic calls involving him, but that none lead to charges, and that he had an incident where he was significantly over the legal limit for crappies a couple of years ago.
Then this article is geared towards "It makes no sense" and is a biased piece of trash.
If the man has a history of domestic violence, that information is relevant to the story.
Instead, this story is trying to create the impression this is an isolated incident, started by someone with an evil assault rifle and a confrontation between gun nuts where words may or may not have been exchanged.
I notice the part "no one knows what words may have been exchanged" is a blatant attempt at blaming the victim, because obviously a white man with a gun=racist=hate speech, which obviously incited the perpetrator.