Ah, I just looked back at the article. It does say that he suffered multiple concussions during his football career.
This makes me lean even more towards the hypothesis that brain damage affected his behavior to the point where he became homicidal. Brain damage can totally change people.
Junior Seau immediately comes to mind.
“This makes me lean even more towards the hypothesis that brain damage affected his behavior to the point where he became homicidal.”
There must be a whole lot of them with concussions in Chicago!