The strongest clues that something was wrong came from the child himself. Last fall, Justin, now 8, began to show increasing signs of emotional turmoil. In September, after moving here from upstate New York, his mother enrolled him in the Brideun School for Exceptional Children in nearby Broomfield. Marlo Payne Rice, the school's director, said Justin did fine for a while, but in November began refusing to do any work, threw temper tantrums, kicked a hole in a school wall and confessed to a social worker that he did not want to live anymore.