"If the authority we desire to use does not come to us through the Constitution, we can exercise it only by usurpation; and usurpation is the most dangerous of political crimes. By that crime the enemies of free government in all ages have worked out their designs against public liberty and private right. It leads directly and immediately to the establishment of absolute rule; for undelegated power is always unlimited and unrestrained."
- President Andrew Johnson, Dec. 3, 1867 message to U.S. House and Senate. [Journal of the Senate of the United States of America, 1789-1873.]