President Barack Obama, first lady Michelle Obama, Malia and Sasha as well as members of Congress and civil rights leaders make a symbolic walk across the Edmund Pettus Bridge, Saturday, March 7, 2015, in Selma, Ala. This weekend marks the 50th anniversary of “Bloody Sunday,’ a civil rights march in which protestors were beaten, trampled and tear-gassed by police at the Edmund Pettus Bridge, in Selma. . (AP Photo/Jacquelyn Martin)