The first vice president to become president on the death of the incumbent, John Tyler (1790-1862) was derided by critics as "His Accidency." In this biography of the tenth president, Edward P. Crapol challenges depictions of Tyler as a die-hard advocate of states' rights, limited government, and a strict interpretation of the Constitution. Instead, he argues, Tyler manipulated the Constitution to increase the executive power of the presidency. Crapol...