SAN FRANCISCO - The Social Security Administration cannot start sending out letters to employers next week containing notification of more serious penalties for knowingly hiring illegal immigrants, a federal judge ruled Friday. Ruling on a lawsuit by the nation's largest federation of labor unions against the U.S. government, U.S. District Judge Maxine Chesney granted a temporary restraining order prohibiting the so-called "no-match" letters from going out as planned starting Tuesday. The AFL-CIO lawsuit, filed this week, claims that new Department of Homeland Security rules outlined in accompanying letters threaten to violate workers' rights and unfairly burden employers. Chesney said the...