As Federal investigators in Tucson try to piece together a detailed picture of Jared Loughner, the suspect in last weekend's mass shopping centre shooting, one question keeps coming back: why were no alarm bells sounded with the authorities before last Saturday about his disturbing behaviour?
Details of how far Loughner strayed from the social mainstream in his thoughts and activities include logs from online chat forums in which he poses questions like: "Does anyone have aggression 24/7?" One the postings, acquired by the Wall Street Journal and published yesterday, touched on cannibalism: "I bet your hungry... Because I know how to cut a body open and eat you for more then a week [sic]."
Most urgently, many in Tucson are asking why Loughner was apparently never referred for treatment or help under the state's mental health programmes? Had that happened, it would have shown up in a background check at any gun shop in the state, making it much harder for him to purchase a weapon.
Last night it emerged that Arizona police flagged Loughner down for driving through a red light, just hours before the shootings. He was given a verbal warning after a wildlife officer from the state's Game and Fish Department decided only to take his licence number. Sheriff's officials also disclosed yesterday that before setting out on his murderous spree, a mumbling Loughner ran into the desert near his home after his father asked him why he was removing a black bag from the boot of a family car.
Why Loughner never received help is not known, but already some mental healthcare advocates are pointing to steep cuts in recent years to the state's programmes for the mentally ill. The budget for mental health coverage in Arizona has been halved in just three years.
The moment he might have come to the state's attention was last autumn when the community college where he was studying suspended him for disruptive behaviour. The school ruled that he would be allowed to return only if he first underwent a professional mental assessment to ensure he wasn't a danger to himself or to others. There is no record that he complied, however.
That Loughner was suffering from some kind of psychotic disorder seems increasingly likely as the information about him accumulates. In an interview with the New York Times, a long-time friend spoke of Loughner contesting that his dream life was what felt real to him, not his actual life.
"Jared felt nothing existed but his subconscious," Zane Gutierrez, 21, explained. "He would ask me constantly, 'Do you see that blue tree over there?' He would admit to seeing the sky as orange and the grass as blue. Normal people don't talk about that stuff."
Police officials meanwhile revealed that during a search of the house where the suspect lived with his parents they found a letter addressed to him from the office of Gabrielle Giffords, the congresswoman shot during the rampage, with the words handwritten on it saying, amongst other things, "Die Bitch".