No political scandal in American history has had a greater impact on America's political consciousness than the rise and fall of the "Tweed Ring" in New York City between 1866 and 1871. In an age ripe with scandal both public and private, the spectacular corruption charged to "Boss" Tweed and his associates-estimates of their extortion range from $20 million to $200 million-became an enduring symbol of the dark side of democratic politics.The Tweed Ring contributed much more than cartoonist impressions: it helped to shape a powerful theory of political reform. It was in truth one of the...