Shafer analyzes Loughner's mug shot:
The shaved character in the movies is almost never happy. Nobody tapping the primal forces he's tapping could ever be happy. But being angry is too clichéd to be accepted. Hence Loughner's bent smile, which recycles Jack Nicholson's psycho grin from The Shining and any number of Bruce Dern and Jack Palance grimaces. Loughner won't be content until people understand that he's a sadistic bastard capable of greater transgressions than shooting innocent people at point-blank range and that killing a 9-year-old only hints at the monster inside him.