Police stand guard outside the prison where the head of Mexico's powerful teachers' union, Elba Esther Gordillo, is being held in Mexico City, Wednesday, Feb. 27, 2013. Mexico's most powerful woman was formally charged with a massive embezzlement scheme on Wednesday, standing grim-faced behind bars live on national television in what many called a clear message that the new government is asserting its authority. (AP Photo/Eduardo Verdugo)
