The trial of Shawna Forde was supposed to be Tucson's big crime story this week. The ex-Seattle prostitute was tipping her hand long before she was accused of shooting and killing a father and his 9-year-old daughter during a robbery last year, telling family members she was planning a new career as leader of an underground militia targeting Mexicans and the federal government. Likewise, Jared Lee Loughner, who was booked into the same Tucson jail as Forde this past weekend, made it clear he was a danger to society long before he was charged Sunday with the attempted killing of a congresswoman and the slayings of six others. "People don't just snap," says Clint Van Zandt, an ex-FBI criminal profiler. Forde, for one, had become the increasingly disturbed leader of a Minuteman group, ranting about immigrants and pulling off armed robberies with the help of Gunny Bush, already wanted for two murders in Wenatchee. Her family informed police, and they were finally but belatedly on her trail as she allegedly turned from robbing Mexicans to killing them. In the case of Loughner, accused of the attempted assassination of Democratic Rep. Gabrielle Giffords, the signals were comparably subtler. Yet he was thought of as an explosive, deranged figure. In his community-college classroom, students and teachers found his anger so threatening that some expected him to pull out a gun and start shooting. As one student put it in an e-mail after an incident last June: "The teacher tried to throw him out and he refused to go, so I talked to the teacher afterward. Hopefully he will be out of class very soon, and not come back with an automatic weapon." Instead he went to a Tucson shopping center Saturday morning with a semi- automatic pistol and began mowing down the crowd attending Giffords' first "Congress on Your Corner" meeting of the year. Loughner now appears to have been stalking Giffords. As far back as 2007, at an earlier Corner event, he asked her "How do you know words mean anything?" and became agitated when she ignored him. He referred to her as a "fake," and friends thought he eventually became fixated on Giffords. In November, he bought a Glock 9mm. More recently he began writing down his plans to assassinate a public official. On Saturday, it all came together: six dead, 14 wounded, including Giffords, so far surviving a gunshot to the head. Loughner is in federal court in Phoenix to enter a plea, while Forde is watching the jury being empaneled for her state-court murder trial in Tucson. It is no small or painless irony that the verdicts to be eventually rendered against both defendants will be based in great deal on what was already known about them.