The Utah mall gunman now has a name. He was an 18-year-old Bosnian immigrant, but beyond that, all that's known about him is that he lived in Salt Lake City with his mother. His aunt said he was "such a good boy." How many times have we heard that before? They're all "good boys" until they pull the trigger. Just ask the relatives of former Eagle Scout and newlywed Charles Whitman (of the bell tower in Texas). Like Whitman, the motives for the Utah shooter's spree are unknown and, with the shooter dead, we may never know. All investigators can do is piece together facets of the shooter's life immediately before his rampage, as Texas officials attempted to do with Whitman. Since no one appeared to know anything about the shooter, he may have been a loner and, like many mass murderers, felt a need to exact revenge on the world he thought had ignored him until he ended his own life. Whitman's autopsy revealed a tumor in his frontal lobe, which may have influenced his behavior. There's no word yet on what, if anything, has been found in the Utah gunman's background that might have served as a trigger for his rampage. But you can expect me to keep an eye on this story, as I have with JonBenet Ramsey/John Mark Karr, the Amish school shooter and the Ipswich Ripper in the past.