When Sonia Sotomayor goes before the Senate next month for her Supreme Court confirmation hearing, the questioning is likely to focus on her work as a civil rights advocate in the 1980s as much as on her nearly two decades on the federal bench. That is because she was a board member of a Puerto Rican advocacy group that sued to overturn New York City's civil service exams and to win more police and firefighter jobs for Latinos. Sotomayor embraced affirmative action and later described herself as leading an "attack" on testing and promotional exams that favored whites and limited...