Thomas A. Bailey and David M. Kennedy, The American Pageant: A History of the Republic, 10th ed., (Lexington, Massachusetts: D.C. Heath and Company, 1994), 430.
The most famous debate came at Freeport, Illinois, where Lincoln narly impaled his opponent on the horns of a dilemma. Suppose, he queried, the people of a territory should vote slavery down? The Supreme Court in the Dred Scott decision had decreed that they could not. Who would pervail, the Court or the people?...His [Douglas'] reply to Lincoln became known as the "Freeport Doctrine." No matter how the Supreme Court ruled, Douglas argued, slavery would stay down if the people voted it down.