I went to grad school in Tucson. Loved the city and region in so many ways. Gun violence perpetrated by the mentally ill was something that this Canadian found hard to get used to.
Although last week’s incident had more human victims, my sense from living there was that it wasn’t unusual to have someone suffering from a mental-illness issue wandering public places with a loaded gun.
One incident at the U of Arizona while I was there involved an individual walking into the grad student computer lab (at a time when I was usually there, but thankfully wasn’t this time), opening fire, missing all the people but destroying two computers, and then wandering down the main campus waving his gun before police grabbed him. It was never clear why he did this (hearing voices, maybe). Subsequent investigation revealed he had long been in treatment from mental illness, but that this did not prevent him from purchasing the firearm legally the previous week because mental health records cannot be used in background checks.
Yes this story is anecdotal but maybe the answer to why certain people in certain places commit these mass murders is a combination of less help for the mentally ill combined with slightly easier access to weapons.