NYT : As the authorities attempted to piece together what prompted a troubled young man to go on a shooting rampage here that killed six people, including a federal judge, and gravely wounded Representative Gabrielle Giffords, they called for the public’s help in finding a possible accomplice who was still at large. Ms. Giffords, 40, an Arizona Democrat, was among at least 12 people wounded in the shooting outside a supermarket where she was meeting with constituents on Saturday morning. She remained unconscious and in critical condition Sunday morning at the University Medical Center in Tucson, where she had been operated on by a team of neurosurgeons. Among those killed were John M. Roll, 63, the chief judge for the United States District Court for Arizona, and Gabriel Zimmerman, 30, who was the director of community outreach for Ms. Giffords. The others who died were identified as Christina Green, 9; Dorothy Morris, 76; Dorwin Stoddard, 76; and Phyllis Schneck, 79. Darci Slaten, a s...