 Ignacio Flores-Figueroa, an illegal alien from Mexico, used a counterfeit Social Security card bearing his real name and a false Social Security number to obtain employment at a steel plant in East Moline, Illinois.Though he did not know it, the number belonged to a real person, a minor.The question in the case was whether workers who use false Social Security and alien registration numbers must know that they belong to a real person to be subject to a two-year sentence extension for "aggravated identity theft."